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Global air travel: toward concentration or dispersal?
Journal of Transport Geography 11 (2003) 83–92 www.elsevier.com/locate/jtrangeo
Global air travel: toward concentration or dispersal? Kevin OÕConnor
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Department of Urban Planning, Faculty of Architecture, Building and Planning, University of Melbourne, Parkville 3101, Australia
Abstract The geography of airline passenger movement through the major cities of the world has changed between 1990 and 2000. The change has been at the expense of the very large global cities and major hubs in favour of a group of next largest cities. It has been detected by comparing the shares of total passenger movement through cities in two separate ways, and by exploring changes in the connectivity between cities over a similar time period. The new pattern reflects the use of new aircraft technology, changes in the location of demand for air travel associated with a broadening in the global linkages between cities, new regulatory arrangements and airline corporate strategies. The implications are that the pressures for airport planning will be felt in a new set of cities, although because the share of passenger traffic through the very large global cities is still high they will remain a major focus for airport planning and management action in the immediate future. Ó 2003 Elsevier Science Ltd. All rights reserved. Keywords: Concentration; Dispersal; Global cities; Global city regions; Hub airport; Connectivity
1. Background to the research The research is designed to establish the extent of change in the spatial development of transport networks at the national and continental scale. The heritage of this work lies in the models reviewed by Hoyle and Smith (1998), which draw their inspiration from the pioneering work of Taaffe, Morrill and Gould. These approaches have rarely been considered from the perspective of air transport. In one example, Rimmer (1991) produced a model predicting very large airports would be the next stage in the development of air networks, while OÕConnor (1995a) has shown how airport development has moved from a linear and dispersed pattern to a concentrated one as technology and markets have changed. The current paper is designed to deepen these perspectives by exploring recent changes in airport and airline activity as reflected in passenger movements. Put simply the paper is designed to assess and account for the extent to which air traffic has moved away from major hubs, or whether GrahamÕs (1997, 15) observation of the ‘‘inexorable processes of spatial concentration’’ is still an accurate assessment of the
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Fax: +613-8344-5532. E-mail address: [email protected] (K. OÕConnor).
changes in traffic patterns. The latter idea, consistent with the framework presented in OÕConnor (1995a) and Rimmer (1991) stems largely from the gradual refinements in technology that culminated in the Boeing 747, reinforced by the hub and spoke strategies of airlines in the US initially, and later elsewhere in the world. At the international scale, Lobbenburg (1994) argues this outcome was reinforced by the bilateral system, which often limited traffic to negotiated city pairs; not withstanding the apparent interest in de-regulation, the bilateral system remains a strong component of the management of air traffic. Long term studies like those of Rimmer and Davenport (1996), OÕConnor (1995b) and OÕConnor and Scott (1992), as well as shares of traffic at global cities assembled by Keeling (1995) confirm that concentration of traffic at a small number of cities has been the main outcome up to around 1990. The link between air travel and business networks (shown by Ivy et al., 1995) as well as the concentration of major tourist and convention destinations (shown by Judd, 1999) confirm that concentration of air traffic at a few nodes has some powerful foundations. Given that background, models of spatial development that suggest greater concentration, like RimmerÕs (1997) port model, seem accurate predictions of the geography of air travel in the future. However, there are reasons to think this trend may have changed in the 1990s, and dispersal of traffic toward next-sized city airports may
0966-6923/03/$ - see front matter Ó 2003 Elsevier Science Ltd. All rights reserved. doi:10.1016/S0966-6923(03)00002-4
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be occurring. That conjecture lies at the core of this paper.
2. Factors shaping a new global geography of air travel 2.1. The demand for air travel Much urban research in the 1990s established that the globalisation of economic activity was felt in particular in a few very large cities with special roles in the worldÕs finance, banking and corporate activities. These places have been labelled ‘‘global cities’’. Empirical results expressed initially by Keeling (1995) and subsequently by Smith and Timberlake (1998) confirm that the hierarchy of these global cities expressed in terms of their influence in global capitalism (Sassen, 2000) closely parallels the hierarchy of airports. Hence it would seem that the character of the global geography of airports is shaped by the forces associated with global city development. That means the continuation in the significance of the global cities will maintain the dominant role of a few very busy airports in the global network. That thinking is reinforced by the adoption of a broader sectoral and spatial framework to understand the urban impact of globalisation. This perspective, outlined in a collection of papers edited by Scott (2001), introduces the idea of a Global City Region, and acknowledges the economic significance of a wide range of activities that may operate from suburban locations and adjacent cities outside the traditional focus of the inner city and the CBD. This perspective has some special implications for air traffic. First, it substantially increases the potential number of travellers that will use the city-region airport as many of the businesses within the wider region will have global contacts. More importantly, many city regions at this larger scale are served by more than one airport, which provides more air passengers. Data displayed by Pels et al. (2001) for the Bay Area shows the passenger catchments of Oakland, San Jose and San Francisco airport overlap and illustrate how a city region can be served by three airports. In Los Angeles, 80% of the passengers within a 60 min radius of Orange County Airport are closer to Long Beach or Ontario, illustrating again the overlap between airports in these large regions (Airline Industry Information, 2000). Over time, the number of airports that are seen as part of a global city region might in fact increase as smaller carriers, charter operators and domestic and regional market operators use these smaller airports to meet demand. In the London case traffic through Stansted and now Luton (Shifrin, 1997) meet demand from the London global city region. In Europe, Ryanair delivers passengers to Frankfurt–Hahn which is 100 km away from Frankfurt, but regarded as ‘‘Frankfurt’’ for Ryanair services (The Economist,
2002a). In the analysis that follows, this effect will be incorporated into traffic counts for 17 cities listed in Appendix B. In effect the paper is really reporting about passenger movement in cities rather than at airports. Although the global city region idea is a powerful one, some recent thinking has suggested that the globalisation of economic activity is beginning to influence urban development through a wider array of activities than banking, finance and corporate control (Storper, 2000). As a result, it is possible that firms located in cities other than those commonly labelled as ‘‘global cities’’ might have become more involved in global air travel than was the case in the past. This is well illustrated in the location of high technology activity in the US. Florida and Gates (2001) produce a list of the US top 10 high technology centres; they show that San Francisco, Boston, Seattle, Washington and Dallas rank ahead of the global cities of Chicago and Los Angeles while Atlanta and Phoenix are ranked ahead of New York. In Europe, a recent analysis of innovative European cities (Simmie, 2001) reported on Milan, Amsterdam and Stuttgart as well as London and Paris. Corroborative evidence of the steady change in the role of the smaller cities comes from reports of the incorporation of a number of them into larger urban regions via inter-firm links and travel-to-work patterns (Dematteis and Governa, 1999; Warneryd, 1999). At the same time analyses of employment change in the UK (Breheny, 1999) and Germany (OECD, 1999) have found cities other than the commonly labelled ‘‘global cities’’ have played a significant role in total employment growth over the recent decade. Hence on the demand side of travel, there may be reason to expect that the pattern of world air travel might be changing to involve a set of next largest cities, those outside the usual list of the worldÕs global cities. Pearson (1997) research on traffic across the North Atlantic illustrates the effect of that change. Although the big hubs of London (especially) and New York are still the dominant airports in North America–Europe traffic, the greatest growth in shares of traffic have been recorded in places like Amsterdam, Zurich and Dublin in Europe, and Memphis, Detroit and Minneapolis in the US. DetroitÕs role is significant in this respect; the data shows it has tripled its share of trans-Atlantic traffic in five years. San Francisco is more prominent than it once was. This information confirms a shift away from the global cities. In another part of the world, the rapid growth of air services to Chinese cities especially Shanghai, Beijing and Guangzhou, along with new airport infrastructure at places like Osaka and Kuala Lumpur has provided opportunities for traffic growth outside the originally dominant places like Tokyo, Hong Kong and Singapore. These examples suggest that the pattern of air travel might be changing. That change might be reinforced by some changes in aircraft technology outlined below.
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2.2. Aircraft technology Shifts in aircraft technology associated with greater speed, carrying capacity and distances between refuelling have had an important influence on the evolution of the geography of air traffic. They were illustrated in changes in the Qantas service network between 1970 and 1990 where smaller city airports were bypassed by nonstop services, and some concentration of traffic at larger city airports occurred (OÕConnor, 1995b). There have been three important changes in aircraft technology in the 1990s that might continue to change patterns of traffic. The first was the introduction of mid-sized long haul aircraft (the Boeing 777 and the Airbus 340), specifically designed (in the case of Boeing, as discussed by Sabbagh (1996) to fly the ‘‘thin’’ routes; indeed one commentator labelled these aircraft ‘‘the hub slayers’’ (The Economist, 1995). These aircraft have been a significant factor in the changes in trans-Atlantic travel in favour of some smaller cities as discussed by Pearson (1997) and earlier by ter Kuile (1997). The change in aircraft has been assisted by changes in navigation and air route administration involving trans-polar routes which has reduced flying times between Europe and North America, and also from airports in the Asia Pacific region to both North America and Europe (Ionides, 2001). Taken together these changes may have helped the dispersal of traffic away from the global cities. A second technical shift has involved the refinement of engine performance, along with management of passenger and freight loads, to create 13–15 h point-topoint services. Extended range 747s, 777s and A340– 500s have made it possible to fly direct between places like Chicago and Hong Kong, New York and Hong Kong and Los Angeles and Singapore. Those routes however have major global city regions at one or both ends, so this technology could maintain the current levels of concentration of traffic. Where the aircraft using these routes are smaller than the 747–400 it is possible that some smaller markets will get more direct international air services. However, the number of these very long haul routes is small, so the overall effect will not be great. A third change in aircraft technology in recent years has been the introduction of regional jets (Pilling, 2001). These have expanded rapidly in the US market in particular, and a little slower in Europe, replacing major carriers in many services (Bombeau, 2001). Over time these aircraft have ‘‘been utilised to substitute or supplement mainline services on some routes and replace turbo-prop services on others. They are also used to start services between new city pairs or perhaps longer routes which bypass a hub’’ (Shrifin, 2001, 51). In many of those applications, the regional jet is contributing to the dispersal of traffic, but at the same time they have
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made it possible to extend the catchment area of an airport, so they could in fact be contributing to the concentration of traffic. The changes outlined above have been reflected in debate about new aircraft design. Opinions differ on the likely pattern of demand for new aircraft; as Zuckerman (1998) showed, Boeing believe the future lies in the midsized, long range aircraft, while Airbus are planning the Airbus 380 which is predicated on very large hub-to-hub traffic in an aircraft larger than the Boeing 747. These different expectations show very clearly that there is an issue about the scale and direction of traffic patterns in the future. 2.3. Regulation Regulatory change and privatisation has opened up competition very rapidly in a number of markets (OÕConnor, 1998), seen in a first and second wave of new airlines; the second wave seem to have had greater success than the first as they have set out to serve different markets, with different services, often relying upon smaller city pairs as a base for their growth. However, reviews of the airline industry show that it has been slow to change its structure when compared with other industries. OÕToole (2002, 67) suggests that the airline industry has not taken advantage of the benefits that globalisation has wrought in other industries. ‘‘The signs suggest this industry is yet to step up to the challenge of addressing new global markets. Its preoccupations still rest heavily on supply side issues driven by measures of process efficiency, asset utilisation and volume growth, not to mention an obsession with consensus and standards’’. Other observers note the paradox that the industry that has contributed so much to the globalisation of the world economy remains itself nationalised and constrained by national regulation. These conservative elements of the character of the airline industry might in fact contribute to the concentration of traffic identified earlier. Hence there may be some built-in forces that limit the dispersal of traffic from global to next-sized cities. Some change in the industry has been achieved through alliances between carriers, a path that Oum and Yu (1998, 17) believe will ‘‘certainly result in the emergence of truly global airlines’’. A survey by Airline Business (Pinkham, 2001) found five groupings of airlines account for almost 60% of world air traffic, so the way alliances shape air traffic patterns is important to understand. Analysis by ter Kuile (1997) suggests alliances could be a force for dispersal as code sharing can increase loads on feeder routes, so stimulating the movement of people through smaller cities. At the same time though, the alliances could in fact bulk traffic at global cities, as they can allow better access to slots at congested airports for alliance members. Taken together
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those factors could maintain or extend the shares of total air traffic at these airports. PearsonÕs (1997, 51) study of the North Atlantic suggested ‘‘alliances do shift market share significantly and are often critical to the growth of airports and individual markets particularly when they allow strong hubs to be connected to each other’’. One example provided was the growth of traffic at both Detroit and Amsterdam associated with the KLM-North West Alliance. Hence it is possible that alliances provide opportunities to disperse traffic to next-sized city airports on international routes so long as the member carriers have services to these airports. The outcomes on traffic patterns can vary. As Pearson (1997, 51) found: ‘‘hubbing is opening up the US end of the market, with an increase in the number of significant gateways, but gateway airports are not on the increase in Europe’’. 2.4. Airports Airports themselves have been an influence on the change in the pattern of traffic. Field (2001) outlines the capacity problems at an increasing number of airports in the US and suggests the use of slot- and landing-pricing might be on the increase. This could have the effect of moving some traffic to other airports, but could also mean that some flights are re-scheduled to other times of the day. Over a longer time period and at a wider scale DempseyÕs (2000) global survey showed that additional airport supply has provided new opportunities for traffic. That can be seen in Europe where Munich and Milan provided new international facilities away from the traditional concentrated markets of the north–west of that continent, while Osaka, Kuala Lumpur and some Chinese cities have also provided greater capacity for carriers. Debate has continued about new airports in some cities but the experience with the political problems of their planning and construction, witnessed at Narita, could mean new airports will be few in number. Many cities will follow ChicagoÕs lead and expand existing facilities. One approach to the congestion problem is to reduce the number of takeoffs and landings by using larger aircraft. That is a signal in favour of the big next generation aircraft, but that may be a simplistic prediction. The problems of airport congestion, and the opportunities created by new facilities, suggest that some dispersal of traffic might occur, and so reduce the role of the global city airports within overall traffic patterns. This review of the key influences on air travel patterns in a global system shows outcomes depend upon a complex and inter-dependent set of forces involving aspects of the demand for air travel, and supply side factors such as airline operation and regulation, and airport management. The paper uses data on passenger traffic at airports to explore the extent to
which these forces have in fact re-shaped the geography of air traffic between 1990 and 2000. This period corresponds to the rise of alliances, and the introduction of the smaller long range and regional jets, and the opening of new airports in a number of destinations.
3. An approach to research on air travel patterns The approach to the research reported here was built on two foundations. The first identified changes in the share of a total of the passengers counted at the worlds busiest 100 airports classified into groups of cities and the second measured the connectivity of some of these airports to others in the world. The first approach involved two separate classifications. One used a classification of the worldÕs cities developed by a research group at Loughborough University and another used the rankings on airport traffic counts produced by Airports Council International (ACI). The classification of cities developed by the Global and World City project (GaWC) at Loughborough University is based upon a study of the location of major corporate activities such as head offices of large companies, banking and corporate services like accountancy, law and financial services (Beaverstock et al., 1999). The classification is well suited to this particular study as it provides categories of places based on an understanding of the location of business, and the broadly-defined corporate influence of a place, which is known to have a major influence on its air traffic. The analysis identified the shares of passengers at each category of city for 1990, 1995 and 2000. Data was available for 83 of the 122 cities in the Beaverstock et al. (1999) classification for the three years. The 1990 data for five cities was derived from an IATA source. The actual cities used in the analysis are listed in Appendix A. A feature of this classification is that some places that are known to be busy airports (Atlanta in particular) do not figure prominently in the upper levels of the classification as they do not have major corporate or other influence in the global economy. In the same vein, a place like Brussels which is not significant in air traffic terms is ranked in a higher group due to its political and business role in Europe. For that reason, the data was also assembled for the top 100 airports as ranked by the ACI. This data is not constrained by missing information: there is a list of the top 100 for each of the three years. There is some change in the membership and rank within the lists as a small number of airports moved into and out of the list over the decade. The lists were not corrected for that change, as what was needed was a simple measure of the total passenger movement. Because several airports within the top 100 were merged into a single city entry as shown in Appendix B the
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approach had to include airports ranked down to around 110 to create the top 100 cities. Though the great attraction of the data used in this first stage of the analysis is its accessibility and relatively low cost, it has a particular weakness in that it is using passengers counted at airports, rather than passengers travelling between cities. That is a problem especially where the hubbing strategy employed by airlines will drive up passenger movement at particular cities. For those places the level of passenger movement does not really reflect the role of that city as a destination, although it does show its importance in the broad pattern of air transport. To deal with this weakness a second foundation was laid under the study. This utilised data developed by Timberlake et al. (2000) on the actual travel between cities for 1991, 1994 and 1997. The data (made available as part of the Global and World City project at Loughborough University) ranks cities by their connectivity to all other places. It is scaled to one for the most connected city (which is London in all years). The research was able to explore the extent to which the connectivity of places has changed for different levels in the airport passenger hierarchy. Although this data is unique, and in its web-based format makes it easily accessible, it too has some unusual characteristics. Even in 1997, airports like Atlanta and Dallas are not included, while Abidjan, Harare and Lagos are represented in all three years. In addition, the data covers almost all cities in the first two Loughborough GaWC classification, but only around two thirds of those in the third category. Hence all the data have some particular limitations. The three cross-cutting approaches that are used compensate in part for these weaknesses and will provide the insight needed to address the issue at the core of the paper. Prior to outlining the results it is important to repeat that the passenger numbers used were for cities, including multiple airports where appropriate. This will tend to bias the data in favour of the very large global cities as some are served by three or four airports. This affect was most obvious in the case of London, New York and Los Angeles.
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4. The geography of world air passenger traffic 4.1. Passengers at global cities The distribution of passengers in the categories identified by the GaWC classification of cities is displayed in Table 1, and the change in their passenger numbers is shown in Table 2. The first table shows that during the 1990s there was a small but steady shift in share of total passengers away from the dominant global cities in the alpha category, toward the next group in particular, as well as toward the third category of city. Significantly, the third category of city includes national capitals like Stockholm, second and third ranked national cities like Atlanta, Boston, Melbourne, and Barcelona, along with growing Asian destinations like Bangkok, Taipei and Kuala Lumpur. This group accounted for the largest share of passenger movement in 2000, although it is important to note that there are 27 cities in this group compared to the 10 in the alpha group. That shift is conformed by the information in table two, where the percentage change in the number of passengers moving through each category of airports is greatest for the beta group, while the absolute growth is greatest in the gamma group. The information on the average passenger movement at each airport casts a different light however; the alpha group on average handle almost double
Table 1 Shares of world airport passengers at groups of cities 1990–2000 Category of city
Number of cities in category
Alpha Beta Gamma Delta
10 8 27 34
1990
1995
2000
35.6 12.0 34.0 18.4
34.3 13.1 34.1 18.5
33.5 14.0 34.4 18.1
100.0
100.0
100.0
Source: Airports Council International: Worldwide Airport Traffic Report (1990, 1995, 2000), Geneva. Airports Council International.
Table 2 Airport passengers and change in airport passengers at groups of cities 1990–2000 (million passengers) Category of city
Number of cities in category
1990
1995
2000
Change 1990–2000
Percentage change 1990–2000
Alpha Average Beta Average Gamma Average Delta Average
10
458,313 45,831 154,475 19,309 437,999 16,222 237,447 6983
541,202 54,120 206,490 25,811 538,331 19,827 293,971 7763
680,223 68,022 283,349 35,418 698,463 25,869 369,585 10,781
221,910 22,190 128,874 16,109 260,464 9646 132,138 3886
48.4
number of passengers per city 8 number of passengers per city 27 number of passengers per city 34 number of passengers per city
83.4 59.4 55.6
Source: Airports Council International: Worldwide Airport Traffic Report (1990, 1995, 2000), Geneva. Airports Council International.
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the number of passengers as the beta group. Taken together these tables show there has been change in the distribution of air passengers among cities, with some gains felt in the cities in the third ranked group in particular. The role of the very large airports has not changed significantly however. Given that the approach to data assembly was biased a little in favour of the alpha cities (as seven in the group have multiple airports) this shift is even more significant. 4.2. A passenger hierarchy of cities The research also explored the distribution of passengers between airports arrayed by absolute size, rather than by function or influence. This approach meant that US airports like Atlanta, Miami and Las Vegas that have high passenger numbers are given greater prominence. In addition, toward the bottom end of the list many smaller airports in the US (e.g. Raleigh–Durham), Europe (e.g. Nice) and elsewhere (e.g. Busan and Kaoshiung) are included; these places do not figure in the functional classification developed by the GaWC research group. Their inclusion here might tap the dispersal of activities in parts of manufacturing and tourism associated with globalisation as discussed earlier. For convenience, the top 100 airports listed by the ACI have been broken down into four categories as shown in Table 3. The data in Table 3 confirm the output of the first stage of the research. The share of all passenger move-
Table 3 Share of passengers at the top 100 airports 1990–2000 Rank Top 10 Ranked 11–20 Ranked 21–50 Ranked 51–100
1990
1995
2000
36.3 15.7 25.2 22.8
32.9 15.5 28.1 23.5
31.0 14.9 29.4 24.7
100.0
100.0
100.0
Source: Airports Council International: Worldwide Airport Traffic Report (1990, 1995, 2000), Geneva. Airports Council International.
ment through the top 10 airport cities (six of which are multiple airport cities) has been declining, along with the share recorded in the next group, while the two groups of smaller cities have attracted increased shares of passengers. In fact the passenger traffic through the cities ranked 21–50 is now much closer to that recorded through the top 10, whereas there was a major difference in their shares of traffic just 10 years earlier. Table 4 confirms that the third group of 30 cities has recorded a very substantial increase in passenger movement, although on average cities in that group account for half the growth of the average city in the top 10; average passenger movement at the latter is over three times that recorded at the average third category city. This information confirms that while the very large cities remain prominent in air passenger movement there has been a shift away from the big airport cities, and the gains have been in a third ranked group. 4.3. Measuring travel between airports The measures reviewed above are based on counts of people moving through airports. In the second stage of the research information on the linkage between those airports was used. This involved using connectivity indices calculated by Timberlake et al. (2000) for groups of cities in the GaWC classification, which are displayed in Figs. 1 and 2 and cities in the alpha and beta categories. Because of the large number of cities in the gamma category indices are displayed in Table 5. Fig. 3 shows the indices at different levels in the traffic hierarchy. The index displayed in the graphs has been expressed in a range from 0 to 1000, rather than 0–1. A common element in the diagrams and tables is that connectivity rose for many cities up to 1994, but declined after that date. That is most apparent for the cities in the alpha category other than London. There are some cities that have recorded steady increases in connectivity however. Significantly they are a couple in the beta category (Mexico City and Seoul), those named in the first part of Table 5, and cities ranked at 20, 30, 40
Table 4 Passenger traffic at the top 100 airports 1990–2000 (million passengers) Rank
1990
1995
2000
Change 1995–2000
Percentage change 1990–2000
Top 10 average number of passengers per city 11–20 Average number of passengers per city 21–50 Average number of passengers per city 51–100 Average number of passengers per city
560,213 56,021 241,888 24,188 389,594 12,986 353,386 7067
653,662 65,366 308,743 30,874 558,783 18,626 469,825 9396
811,074 81,107 392,010 39,201 767,412 25,580 646,272 12,925
250,858 25,085 150,122 15,012 377,818 12,593 292,886 5858
44.8 62.0 96.9 82.8
Source: Airports Council International: Worldwide Airport Traffic Report (1990, 1995, 2000), Geneva. Airports Council International.
K. OÕConnor / Journal of Transport Geography 11 (2003) 83–92
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Fig. 1. Connectivity indices for alpha global cities 1991–1997. Source: Timberlake et al. (2000).
Fig. 2. Connectivity indices for beta category global cities 1991–1997. Source: Timberlake et al. (2000).
and 50 in the passenger hierarchy. Taken together this information confirms the emphasis of change in the distribution of passenger numbers toward the second and third ranked cities, as the previous analysis had exposed. Smith and Timberlake (2002) have analysed this data in a different way. They use 22 cities drawn mainly from the alpha and beta categories in the GaWC classification. They find that between 1991 and 1994 there is a bunching of the mid-sized cities in their sample around a similar value of the index. That outcome involves San Francisco, Milan, Madrid, Chicago, Amsterdam and Zurich. The bunching weakens a little by 1997. For them the result suggests the simple hierarchical differentiation in the role places play in the global network has begun to weaken. Interpreted in the context of the present paper, that seems consistent with a stronger role of second and third ranked cities as origin and destinations.
5. Implications The shift in traffic detected here is likely to be related to changes in aircraft technology, a gradual deregulation of air travel (induced in part through alliances and assisted by new small carriers) and changes in the production systems of firms in a range of industries. These changes represent another stage in the way globalisation is shaping the cities within the world economy. For transport geography, the information means that analytical frameworks need to look beyond continuation of the role of very large cities and incorporate a greater role for next-sized cities. For airport planning and development, the results imply that pressure to provide additional capacity to manage air passenger numbers might move away from the very large cities to those in the next rank and below. The research also implies that the long term evolution of air travel probably lies in the mid-sized and smaller
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Table 5 Connectivity indices for gamma category cities 1991
1994
1997
Cities recording steady increase in connectivity: 1991–1997 Caracas 186 192 216 Copenhagen 300 347 356 Osaka 154 195 364 Manila 261 285 292 Prague 126 184 195 Santiago 178 235 243 Washington 188 204 252 Cities recording uneven change in connectivity: 1997 level > 1991 level Amsterdam 575 677 614 Boston 189 245 239 Kuala Lumpur 245 242 311 Montreal 152 171 155 Stockholm 241 214 259 Warsaw 181 145 183 Cities recording uneven change in connectivity: 1997 level < 1991 level Bangkok 492 504 444 Budapest 163 47 41 Houston 238 260 202 Jakarta 159 188 122 JoÕburg 200 94 101 Miami 530 575 533 Taipei 287 257 259
aircraft capable of providing links between those cities in the middle and lower levels of the top 100 airports identified here. Perhaps there is less scope than some people have predicted for the extended jumbo that is being planned by Airbus. That observation is consistent with a conclusion of a recent overview of the corporate competition between Boeing and Airbus: Ô. . .most of the competition will continue to be in smaller aircraft’’ (The Economist, 2002b, 73). On another tack, as the pattern of air passenger traffic re-
flects the location and activity of the economy, any greater dispersal of global activity toward cities in the second level in the hierarchy will continue the shift of traffic away from the top ranked global cities. However, it is also important to recognise that a small number of these global cities remain the dominant feature of world aviation. In fact in 2000, the airports in four city-regions, London, New York, Chicago and Tokyo, accounted for 23% of the total passenger movement through the worldÕs 100 busiest airports. The continued role of these big city regions will keep the planning and management of airport infrastructure at the forefront of airport planning in the immediate future. That planning may need to recognise the use of the very large Airbus 380 for hub-to-hub services. At the time of writing it appears that the September 11, 2001 terrorist attack, along with the slowing in the world economy, has changed both the number of people flying and the cities they want to visit. Although too early to analyse in the format outlined above, one response seems to have been a shift away from smaller markets to concentrate traffic on larger centres. As an illustration, Qantas withdrew from many of the routes to smaller Asian and European cities and maintained services on its routes to London and Los Angeles. However, by February 2002 Airline Business (2002, 24) reported that ‘‘middle ranking US airlines have recovered faster’’ but acknowledged that it was too early to say whether this represented a major structural shift in the industry or its operations. This suggests corporate change in the airline industry could emerge as a key influence upon the distribution of passenger numbers. If that change involves large airlines losing market share to smaller companies, there may be a flow-on effect into the geography of passenger movement as the
Fig. 3. Connectivity indices for cities ranked in passenger hierarchy 1991–1997. Source: Timberlake et al. (2000).
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very large airlines all tend to have major city airports as their home base. A diminution in their corporate activity may be felt in a diminution in their traffic and hence passenger movement. On balance then, the research reported here, along with current changes in airline operation, airport management and the distribution of business all seem to point to a continued shift in passenger traffic away from very large cities toward those next in rank.
Acknowledgements The author thanks John Bowen for an invitation to join a panel on Pacific Rim Air and Maritime Transport at the American Association of Geographers where an initial draft of this paper was discussed. Travel funds from the Faculty of Architecture, Building and Planning at the University of Melbourne made it possible to attend the AAG meeting and also to purchase the data used here. Staff in the Research Division of the Airports Council International, Geneva were very helpful in the prompt delivery of the data. In addition thorough reviews by two anonymous referees substantially improved the paper, one in particular suggesting the use of the airport averages used in Tables 2 and 4. Thanks also to the Global and World City Project at Loughborough University for making available a wealth of information, including in particular the David Smith and Michael Timberlake data base on airport connectivity.
Appendix A. The global and world cities classification, with cities included in the analysis Alpha world cities: Chicago, Frankfurt, Hong Kong, London, Los Angeles, Milan, New York, Paris, Tokyo, Singapore. Beta world cities: Brussels, Madrid, Mexico City, Moscow, San Francisco, Sao Paulo, Seoul, Sydney, Toronto, Zurich. Gamma world cities: Amsterdam, Atlanta, Bangkok, Barcelona, Boston, Buenos Aires, Budapest, Copenhagen, Dallas, Dusseldorf, Geneva, Hamburg, Houston, Istanbul, Jakarta, Manila, Melbourne, Miami, Minneapolis, Montreal, Munich, Osaka, Rome, Stockholm, Taipei, Warsaw, Washington. Delta cities: Adelaide, Auckland, Birmingham, Bogota, Bologna, Brazilia, Brisbane, Bucharest, Calgary, Cairo, Colombo, Columbus, Cleveland, Cologne, Detroit, Edinburgh, Glasgow, Gothenburg, Kansas City, Leeds, Lisbon, Manchester, Marseille, Montevideo, Oslo, Richmond, Rotterdam, Riyadh, St. Petersburg, Seattle, Stuttgart, Tijuana, Turin, Vancouver.
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Appendix B. Multiple city airports Chicago: Dallas: Houston:
OÕHare, Midway, Meigs Field. Dallas-Fort Worth, Love Field. George Bush International, WP Hobby. Jakarta: Halim Perdankusuma, Soekarno Hatta. London: Heathrow, Gatwick, Stansted, Luton, City. Los Angeles: LAX, Long Beach, Ontario, Burbank, Santa Barbara, Santa Ana. Las Vegas: Henderson, McCarran, North Las Vegas. Milan: Linate, Malpesa. Montreal: Dorval, Mirabel. Moscow: Shermetyevo, Vnukovo. New York: JFK, Newark, La Guardia, Newburg, White Plains. Osaka: Kansai, Itami. Paris: Charles de Gaulle, Orly. Rome: Ciampino, Fiurmicino. San Francisco: Oakland, San Francisco, San Jose. Tokyo: Narita, Haneda. Washington: Baltimore/Washington, IAD, Washington National.
References Airline Business, 2002. Small is beautiful...but it is better? Airline Business 18 (2), 24–27. Airports Council International, 1990, 1995, 2000. Worldwide, Airport Traffic Report. Airports Council International, Geneva. Airline Industry Information, 2000. No Demand for Second El Toro Airport. Airport Industry Information May 12, 2000. Beaverstock, J.G., Taylor, P., Smith, R.G., 1999. A roster of world cities. Cities 16, 445–458. Bombeau, B., 2001. Regional aircraft market jitters. Interavia Business and Technology 57 (622), 36–39. Breheny, M., 1999. Introduction. In: Breheny, M. (Ed.), The People. Where will they work? Town and Country Planning Association, London, pp. 1–8. Dempsey, P., 2000. Airport Planning and Development Handbook: A Global Survey. McGraw Hill, New York. Dematteis, G., Governa, F., 1999. From urban field to continuous urban settlement networks. European examples. In: Aguilar, A.G., Escamilla, I. (Eds.), Problems of Megacities: Social Inequalities, Environmental Risk and Urban Governance. IGU Commission of Urban Development and Urban life and Institute of Geography, Universidad Nacional Autonoma De Mexico, Mexico City, pp. 543–556. The Economist, 1995. Stretched to the limit. The Economist (June 17), 70. The Economist, 2002a. The pluck of the irish. The Economist (January 26), 61. The Economist, 2002b. Special report: Boeing versus airbus: toward the wild blue yonder. The Economist (April 27), 71–73. Field, D., 2001. Pressure points. Airline Business 17 (6), 64–68. Florida, R., Gates, G., 2001. Technology and tolerance: the importance of diversity to high technology growth. In: The Brookings
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Institution Center on Urban and Metropolitan Policy. Survey series. The Brookings Institution, Washington. Graham, B., 1997. International air transport. In: Hoyle, B., Knowles, R. (Eds.), Modern Transport Geography, second ed. John Wiley, London. Hoyle, B., Smith, J., 1998. Transport and development: theories, models, nodes and networks. In: Hoyle, B., Knowles, R. (Eds.), Modern Transport Geography, second ed. John Wiley, London. Ionides, N., 2001. Transpolar US–Asia routes heat up. Airline Business 17 (4), 27. Ivy, R.I., Fik, T.J., Malecki, E., 1995. Changes in air service connectivity and employment. Environment and Planning A 27, 165–179. Judd, D.R., 1999. Constructing the tourist bubble. In: Judd, D.R., Fanstein, S.S. (Eds.), The Tourist City. Yale UP, New Haven, pp. 35–53. Keeling, D.J., 1995. Transport and the world city paradigm. In: Knox, P.L., Taylor, P.J. (Eds.), World Cities in a World System. CUP, Cambridge, pp. 115–131. Lobbenburg, A., 1994. Government relations on the North Atlantic: a case study of five Europe–USA relationships. Journal of Air Transport Management 1, 47–62. OÕConnor, K., 1995a. Airport development in South East Asia. Journal of Transport Geography 3, 1–18. OÕConnor, K., 1995b. Change in the pattern of airline services and city development. In: Brotchie, J., Batty, M., Blakely, E., Hall, P., Newton, P. (Eds.), Cities in Competition. Longmans, Melbourne, pp. 88–104. OÕConnor, K., 1998. The New Game. Deregulation, Privatisation and the State of the Airline Industry. Critical Matters Series. Public Sector Research Centre and Evatt Foundation. Sydney, University of New South Wales. OÕConnor, K., Scott, A., 1992. Airline services and metropolitan areas in the Asia Pacific region. Review of Urban and Regional Development Studies 4, 240–253. OECD, 1999. Urban Policy in Germany: Towards Sustainable Urban Development. Paris. OECD. OÕToole, K., 2002. Airline industry globalisation. Airline Business 18 (3), 66–67. Oum, T.A., Yu, C., 1998. Winning Airlines: Productivity, and Cost Competitiveness of Major Airlines. Kluwer Publishers, Boston. Pearson, A., 1997. North atlantic shifting sands. Airline Business 13 (8), 46–51. Pels, E., Nijkamp, P., Rietveld, P., 2001. Airport and airline choice in a multiple airport region: an empirical analysis for the San Francisco Bay area. Regional Studies 35 (1), 1–10. Pilling, M., 2001. Regional jets take on defensive role. Airline Business 17 (12), 12. Pinkham, R., 2001. Playing for position. Airline Business 17 (7), 40–41.
Rimmer, P.J., 1991. Mega cities, Multi-layered Networks and Development Corridors in the Pacific Economic Zone: the Japanese Ascendency, in Conference Papers on Transportation and Urban Development. Pacific Rim Council on Urban Development. Third Annual Conference. Centre for Human Settlements and School of Community and Regional Planning, University of British Columbia. Vancouver, pp. 6–56. Rimmer, P.J, 1997. A conceptual framework for examining urban and regional transport needs in South East Asia. Pacific Viewpoint 18, 133–147. Rimmer, P.J., Davenport, S., 1996. Flying from empire to commonwealth 1919–1994. In: Yeung, Y.M. (Ed.), Global Change and the Commonwealth. Hong Kong Institute of Asia Pacific Studies. The Chinese University of Hong Kong. Sabbagh, K., 1996. Twenty First Century Jet: The Making and Marketing of the Boeing. 777. Scribner, New York. Sassen, S., 2000. Cities in a World Economy, second ed. Pine Forge Press, London. Scott, A. (Ed.), 2001. Global City Regions: Trends, Theory, Policy. Oxford UP, London. Shifrin, C., 1997. Luton airport evolving beyond charter niche. Aviation Week & Space Technology 146 (17), 43. Shrifin, C., 2001. Flexible friends. Airline Business 17 (11), 50–52. Simmie, J. (Ed.), 2001. Innovative Cities. Spon Press, London. Smith, D.S., Timberlake, M., 1998. Cities and the spatial articulation of the world economy through air travel. In: Cicantell, P., Bunker, S. (Eds.), Space and Transport in the World System. Greenwood Press, Westport, Ct, pp. 213–240. Smith, D.S., Timberlake, M., 2002. Hierarchies of dominance among world cities: a network approach. In: Sassen, S. (Ed.), Global Networks Linked Cities. Routledge, London, pp. 117– 141. Storper, M., 2000. Globalisation and knowledge flows: an industrial geographerÕs perspective. In: Dunning, J. (Ed.), Regions, Globalisation and The knowledge based Economy London. Oxford UP, Oxford, pp. 42–62. ter Kuile, A., 1997. Hub fever. Airport Business 11 (12), 66–71. Timberlake, M., Smith, D.A., Shin, K.H., 2000. The relative Centrality of Cities based upon Air passenger travel, 1977–1997. Data Set 10. GaWC Study Group and Network. Available from
Global air travel: toward concentration or dispersal? Kevin OÕConnor
*
Department of Urban Planning, Faculty of Architecture, Building and Planning, University of Melbourne, Parkville 3101, Australia
Abstract The geography of airline passenger movement through the major cities of the world has changed between 1990 and 2000. The change has been at the expense of the very large global cities and major hubs in favour of a group of next largest cities. It has been detected by comparing the shares of total passenger movement through cities in two separate ways, and by exploring changes in the connectivity between cities over a similar time period. The new pattern reflects the use of new aircraft technology, changes in the location of demand for air travel associated with a broadening in the global linkages between cities, new regulatory arrangements and airline corporate strategies. The implications are that the pressures for airport planning will be felt in a new set of cities, although because the share of passenger traffic through the very large global cities is still high they will remain a major focus for airport planning and management action in the immediate future. Ó 2003 Elsevier Science Ltd. All rights reserved. Keywords: Concentration; Dispersal; Global cities; Global city regions; Hub airport; Connectivity
1. Background to the research The research is designed to establish the extent of change in the spatial development of transport networks at the national and continental scale. The heritage of this work lies in the models reviewed by Hoyle and Smith (1998), which draw their inspiration from the pioneering work of Taaffe, Morrill and Gould. These approaches have rarely been considered from the perspective of air transport. In one example, Rimmer (1991) produced a model predicting very large airports would be the next stage in the development of air networks, while OÕConnor (1995a) has shown how airport development has moved from a linear and dispersed pattern to a concentrated one as technology and markets have changed. The current paper is designed to deepen these perspectives by exploring recent changes in airport and airline activity as reflected in passenger movements. Put simply the paper is designed to assess and account for the extent to which air traffic has moved away from major hubs, or whether GrahamÕs (1997, 15) observation of the ‘‘inexorable processes of spatial concentration’’ is still an accurate assessment of the
*
Fax: +613-8344-5532. E-mail address: [email protected] (K. OÕConnor).
changes in traffic patterns. The latter idea, consistent with the framework presented in OÕConnor (1995a) and Rimmer (1991) stems largely from the gradual refinements in technology that culminated in the Boeing 747, reinforced by the hub and spoke strategies of airlines in the US initially, and later elsewhere in the world. At the international scale, Lobbenburg (1994) argues this outcome was reinforced by the bilateral system, which often limited traffic to negotiated city pairs; not withstanding the apparent interest in de-regulation, the bilateral system remains a strong component of the management of air traffic. Long term studies like those of Rimmer and Davenport (1996), OÕConnor (1995b) and OÕConnor and Scott (1992), as well as shares of traffic at global cities assembled by Keeling (1995) confirm that concentration of traffic at a small number of cities has been the main outcome up to around 1990. The link between air travel and business networks (shown by Ivy et al., 1995) as well as the concentration of major tourist and convention destinations (shown by Judd, 1999) confirm that concentration of air traffic at a few nodes has some powerful foundations. Given that background, models of spatial development that suggest greater concentration, like RimmerÕs (1997) port model, seem accurate predictions of the geography of air travel in the future. However, there are reasons to think this trend may have changed in the 1990s, and dispersal of traffic toward next-sized city airports may
0966-6923/03/$ - see front matter Ó 2003 Elsevier Science Ltd. All rights reserved. doi:10.1016/S0966-6923(03)00002-4
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be occurring. That conjecture lies at the core of this paper.
2. Factors shaping a new global geography of air travel 2.1. The demand for air travel Much urban research in the 1990s established that the globalisation of economic activity was felt in particular in a few very large cities with special roles in the worldÕs finance, banking and corporate activities. These places have been labelled ‘‘global cities’’. Empirical results expressed initially by Keeling (1995) and subsequently by Smith and Timberlake (1998) confirm that the hierarchy of these global cities expressed in terms of their influence in global capitalism (Sassen, 2000) closely parallels the hierarchy of airports. Hence it would seem that the character of the global geography of airports is shaped by the forces associated with global city development. That means the continuation in the significance of the global cities will maintain the dominant role of a few very busy airports in the global network. That thinking is reinforced by the adoption of a broader sectoral and spatial framework to understand the urban impact of globalisation. This perspective, outlined in a collection of papers edited by Scott (2001), introduces the idea of a Global City Region, and acknowledges the economic significance of a wide range of activities that may operate from suburban locations and adjacent cities outside the traditional focus of the inner city and the CBD. This perspective has some special implications for air traffic. First, it substantially increases the potential number of travellers that will use the city-region airport as many of the businesses within the wider region will have global contacts. More importantly, many city regions at this larger scale are served by more than one airport, which provides more air passengers. Data displayed by Pels et al. (2001) for the Bay Area shows the passenger catchments of Oakland, San Jose and San Francisco airport overlap and illustrate how a city region can be served by three airports. In Los Angeles, 80% of the passengers within a 60 min radius of Orange County Airport are closer to Long Beach or Ontario, illustrating again the overlap between airports in these large regions (Airline Industry Information, 2000). Over time, the number of airports that are seen as part of a global city region might in fact increase as smaller carriers, charter operators and domestic and regional market operators use these smaller airports to meet demand. In the London case traffic through Stansted and now Luton (Shifrin, 1997) meet demand from the London global city region. In Europe, Ryanair delivers passengers to Frankfurt–Hahn which is 100 km away from Frankfurt, but regarded as ‘‘Frankfurt’’ for Ryanair services (The Economist,
2002a). In the analysis that follows, this effect will be incorporated into traffic counts for 17 cities listed in Appendix B. In effect the paper is really reporting about passenger movement in cities rather than at airports. Although the global city region idea is a powerful one, some recent thinking has suggested that the globalisation of economic activity is beginning to influence urban development through a wider array of activities than banking, finance and corporate control (Storper, 2000). As a result, it is possible that firms located in cities other than those commonly labelled as ‘‘global cities’’ might have become more involved in global air travel than was the case in the past. This is well illustrated in the location of high technology activity in the US. Florida and Gates (2001) produce a list of the US top 10 high technology centres; they show that San Francisco, Boston, Seattle, Washington and Dallas rank ahead of the global cities of Chicago and Los Angeles while Atlanta and Phoenix are ranked ahead of New York. In Europe, a recent analysis of innovative European cities (Simmie, 2001) reported on Milan, Amsterdam and Stuttgart as well as London and Paris. Corroborative evidence of the steady change in the role of the smaller cities comes from reports of the incorporation of a number of them into larger urban regions via inter-firm links and travel-to-work patterns (Dematteis and Governa, 1999; Warneryd, 1999). At the same time analyses of employment change in the UK (Breheny, 1999) and Germany (OECD, 1999) have found cities other than the commonly labelled ‘‘global cities’’ have played a significant role in total employment growth over the recent decade. Hence on the demand side of travel, there may be reason to expect that the pattern of world air travel might be changing to involve a set of next largest cities, those outside the usual list of the worldÕs global cities. Pearson (1997) research on traffic across the North Atlantic illustrates the effect of that change. Although the big hubs of London (especially) and New York are still the dominant airports in North America–Europe traffic, the greatest growth in shares of traffic have been recorded in places like Amsterdam, Zurich and Dublin in Europe, and Memphis, Detroit and Minneapolis in the US. DetroitÕs role is significant in this respect; the data shows it has tripled its share of trans-Atlantic traffic in five years. San Francisco is more prominent than it once was. This information confirms a shift away from the global cities. In another part of the world, the rapid growth of air services to Chinese cities especially Shanghai, Beijing and Guangzhou, along with new airport infrastructure at places like Osaka and Kuala Lumpur has provided opportunities for traffic growth outside the originally dominant places like Tokyo, Hong Kong and Singapore. These examples suggest that the pattern of air travel might be changing. That change might be reinforced by some changes in aircraft technology outlined below.
K. OÕConnor / Journal of Transport Geography 11 (2003) 83–92
2.2. Aircraft technology Shifts in aircraft technology associated with greater speed, carrying capacity and distances between refuelling have had an important influence on the evolution of the geography of air traffic. They were illustrated in changes in the Qantas service network between 1970 and 1990 where smaller city airports were bypassed by nonstop services, and some concentration of traffic at larger city airports occurred (OÕConnor, 1995b). There have been three important changes in aircraft technology in the 1990s that might continue to change patterns of traffic. The first was the introduction of mid-sized long haul aircraft (the Boeing 777 and the Airbus 340), specifically designed (in the case of Boeing, as discussed by Sabbagh (1996) to fly the ‘‘thin’’ routes; indeed one commentator labelled these aircraft ‘‘the hub slayers’’ (The Economist, 1995). These aircraft have been a significant factor in the changes in trans-Atlantic travel in favour of some smaller cities as discussed by Pearson (1997) and earlier by ter Kuile (1997). The change in aircraft has been assisted by changes in navigation and air route administration involving trans-polar routes which has reduced flying times between Europe and North America, and also from airports in the Asia Pacific region to both North America and Europe (Ionides, 2001). Taken together these changes may have helped the dispersal of traffic away from the global cities. A second technical shift has involved the refinement of engine performance, along with management of passenger and freight loads, to create 13–15 h point-topoint services. Extended range 747s, 777s and A340– 500s have made it possible to fly direct between places like Chicago and Hong Kong, New York and Hong Kong and Los Angeles and Singapore. Those routes however have major global city regions at one or both ends, so this technology could maintain the current levels of concentration of traffic. Where the aircraft using these routes are smaller than the 747–400 it is possible that some smaller markets will get more direct international air services. However, the number of these very long haul routes is small, so the overall effect will not be great. A third change in aircraft technology in recent years has been the introduction of regional jets (Pilling, 2001). These have expanded rapidly in the US market in particular, and a little slower in Europe, replacing major carriers in many services (Bombeau, 2001). Over time these aircraft have ‘‘been utilised to substitute or supplement mainline services on some routes and replace turbo-prop services on others. They are also used to start services between new city pairs or perhaps longer routes which bypass a hub’’ (Shrifin, 2001, 51). In many of those applications, the regional jet is contributing to the dispersal of traffic, but at the same time they have
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made it possible to extend the catchment area of an airport, so they could in fact be contributing to the concentration of traffic. The changes outlined above have been reflected in debate about new aircraft design. Opinions differ on the likely pattern of demand for new aircraft; as Zuckerman (1998) showed, Boeing believe the future lies in the midsized, long range aircraft, while Airbus are planning the Airbus 380 which is predicated on very large hub-to-hub traffic in an aircraft larger than the Boeing 747. These different expectations show very clearly that there is an issue about the scale and direction of traffic patterns in the future. 2.3. Regulation Regulatory change and privatisation has opened up competition very rapidly in a number of markets (OÕConnor, 1998), seen in a first and second wave of new airlines; the second wave seem to have had greater success than the first as they have set out to serve different markets, with different services, often relying upon smaller city pairs as a base for their growth. However, reviews of the airline industry show that it has been slow to change its structure when compared with other industries. OÕToole (2002, 67) suggests that the airline industry has not taken advantage of the benefits that globalisation has wrought in other industries. ‘‘The signs suggest this industry is yet to step up to the challenge of addressing new global markets. Its preoccupations still rest heavily on supply side issues driven by measures of process efficiency, asset utilisation and volume growth, not to mention an obsession with consensus and standards’’. Other observers note the paradox that the industry that has contributed so much to the globalisation of the world economy remains itself nationalised and constrained by national regulation. These conservative elements of the character of the airline industry might in fact contribute to the concentration of traffic identified earlier. Hence there may be some built-in forces that limit the dispersal of traffic from global to next-sized cities. Some change in the industry has been achieved through alliances between carriers, a path that Oum and Yu (1998, 17) believe will ‘‘certainly result in the emergence of truly global airlines’’. A survey by Airline Business (Pinkham, 2001) found five groupings of airlines account for almost 60% of world air traffic, so the way alliances shape air traffic patterns is important to understand. Analysis by ter Kuile (1997) suggests alliances could be a force for dispersal as code sharing can increase loads on feeder routes, so stimulating the movement of people through smaller cities. At the same time though, the alliances could in fact bulk traffic at global cities, as they can allow better access to slots at congested airports for alliance members. Taken together
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those factors could maintain or extend the shares of total air traffic at these airports. PearsonÕs (1997, 51) study of the North Atlantic suggested ‘‘alliances do shift market share significantly and are often critical to the growth of airports and individual markets particularly when they allow strong hubs to be connected to each other’’. One example provided was the growth of traffic at both Detroit and Amsterdam associated with the KLM-North West Alliance. Hence it is possible that alliances provide opportunities to disperse traffic to next-sized city airports on international routes so long as the member carriers have services to these airports. The outcomes on traffic patterns can vary. As Pearson (1997, 51) found: ‘‘hubbing is opening up the US end of the market, with an increase in the number of significant gateways, but gateway airports are not on the increase in Europe’’. 2.4. Airports Airports themselves have been an influence on the change in the pattern of traffic. Field (2001) outlines the capacity problems at an increasing number of airports in the US and suggests the use of slot- and landing-pricing might be on the increase. This could have the effect of moving some traffic to other airports, but could also mean that some flights are re-scheduled to other times of the day. Over a longer time period and at a wider scale DempseyÕs (2000) global survey showed that additional airport supply has provided new opportunities for traffic. That can be seen in Europe where Munich and Milan provided new international facilities away from the traditional concentrated markets of the north–west of that continent, while Osaka, Kuala Lumpur and some Chinese cities have also provided greater capacity for carriers. Debate has continued about new airports in some cities but the experience with the political problems of their planning and construction, witnessed at Narita, could mean new airports will be few in number. Many cities will follow ChicagoÕs lead and expand existing facilities. One approach to the congestion problem is to reduce the number of takeoffs and landings by using larger aircraft. That is a signal in favour of the big next generation aircraft, but that may be a simplistic prediction. The problems of airport congestion, and the opportunities created by new facilities, suggest that some dispersal of traffic might occur, and so reduce the role of the global city airports within overall traffic patterns. This review of the key influences on air travel patterns in a global system shows outcomes depend upon a complex and inter-dependent set of forces involving aspects of the demand for air travel, and supply side factors such as airline operation and regulation, and airport management. The paper uses data on passenger traffic at airports to explore the extent to
which these forces have in fact re-shaped the geography of air traffic between 1990 and 2000. This period corresponds to the rise of alliances, and the introduction of the smaller long range and regional jets, and the opening of new airports in a number of destinations.
3. An approach to research on air travel patterns The approach to the research reported here was built on two foundations. The first identified changes in the share of a total of the passengers counted at the worlds busiest 100 airports classified into groups of cities and the second measured the connectivity of some of these airports to others in the world. The first approach involved two separate classifications. One used a classification of the worldÕs cities developed by a research group at Loughborough University and another used the rankings on airport traffic counts produced by Airports Council International (ACI). The classification of cities developed by the Global and World City project (GaWC) at Loughborough University is based upon a study of the location of major corporate activities such as head offices of large companies, banking and corporate services like accountancy, law and financial services (Beaverstock et al., 1999). The classification is well suited to this particular study as it provides categories of places based on an understanding of the location of business, and the broadly-defined corporate influence of a place, which is known to have a major influence on its air traffic. The analysis identified the shares of passengers at each category of city for 1990, 1995 and 2000. Data was available for 83 of the 122 cities in the Beaverstock et al. (1999) classification for the three years. The 1990 data for five cities was derived from an IATA source. The actual cities used in the analysis are listed in Appendix A. A feature of this classification is that some places that are known to be busy airports (Atlanta in particular) do not figure prominently in the upper levels of the classification as they do not have major corporate or other influence in the global economy. In the same vein, a place like Brussels which is not significant in air traffic terms is ranked in a higher group due to its political and business role in Europe. For that reason, the data was also assembled for the top 100 airports as ranked by the ACI. This data is not constrained by missing information: there is a list of the top 100 for each of the three years. There is some change in the membership and rank within the lists as a small number of airports moved into and out of the list over the decade. The lists were not corrected for that change, as what was needed was a simple measure of the total passenger movement. Because several airports within the top 100 were merged into a single city entry as shown in Appendix B the
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approach had to include airports ranked down to around 110 to create the top 100 cities. Though the great attraction of the data used in this first stage of the analysis is its accessibility and relatively low cost, it has a particular weakness in that it is using passengers counted at airports, rather than passengers travelling between cities. That is a problem especially where the hubbing strategy employed by airlines will drive up passenger movement at particular cities. For those places the level of passenger movement does not really reflect the role of that city as a destination, although it does show its importance in the broad pattern of air transport. To deal with this weakness a second foundation was laid under the study. This utilised data developed by Timberlake et al. (2000) on the actual travel between cities for 1991, 1994 and 1997. The data (made available as part of the Global and World City project at Loughborough University) ranks cities by their connectivity to all other places. It is scaled to one for the most connected city (which is London in all years). The research was able to explore the extent to which the connectivity of places has changed for different levels in the airport passenger hierarchy. Although this data is unique, and in its web-based format makes it easily accessible, it too has some unusual characteristics. Even in 1997, airports like Atlanta and Dallas are not included, while Abidjan, Harare and Lagos are represented in all three years. In addition, the data covers almost all cities in the first two Loughborough GaWC classification, but only around two thirds of those in the third category. Hence all the data have some particular limitations. The three cross-cutting approaches that are used compensate in part for these weaknesses and will provide the insight needed to address the issue at the core of the paper. Prior to outlining the results it is important to repeat that the passenger numbers used were for cities, including multiple airports where appropriate. This will tend to bias the data in favour of the very large global cities as some are served by three or four airports. This affect was most obvious in the case of London, New York and Los Angeles.
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4. The geography of world air passenger traffic 4.1. Passengers at global cities The distribution of passengers in the categories identified by the GaWC classification of cities is displayed in Table 1, and the change in their passenger numbers is shown in Table 2. The first table shows that during the 1990s there was a small but steady shift in share of total passengers away from the dominant global cities in the alpha category, toward the next group in particular, as well as toward the third category of city. Significantly, the third category of city includes national capitals like Stockholm, second and third ranked national cities like Atlanta, Boston, Melbourne, and Barcelona, along with growing Asian destinations like Bangkok, Taipei and Kuala Lumpur. This group accounted for the largest share of passenger movement in 2000, although it is important to note that there are 27 cities in this group compared to the 10 in the alpha group. That shift is conformed by the information in table two, where the percentage change in the number of passengers moving through each category of airports is greatest for the beta group, while the absolute growth is greatest in the gamma group. The information on the average passenger movement at each airport casts a different light however; the alpha group on average handle almost double
Table 1 Shares of world airport passengers at groups of cities 1990–2000 Category of city
Number of cities in category
Alpha Beta Gamma Delta
10 8 27 34
1990
1995
2000
35.6 12.0 34.0 18.4
34.3 13.1 34.1 18.5
33.5 14.0 34.4 18.1
100.0
100.0
100.0
Source: Airports Council International: Worldwide Airport Traffic Report (1990, 1995, 2000), Geneva. Airports Council International.
Table 2 Airport passengers and change in airport passengers at groups of cities 1990–2000 (million passengers) Category of city
Number of cities in category
1990
1995
2000
Change 1990–2000
Percentage change 1990–2000
Alpha Average Beta Average Gamma Average Delta Average
10
458,313 45,831 154,475 19,309 437,999 16,222 237,447 6983
541,202 54,120 206,490 25,811 538,331 19,827 293,971 7763
680,223 68,022 283,349 35,418 698,463 25,869 369,585 10,781
221,910 22,190 128,874 16,109 260,464 9646 132,138 3886
48.4
number of passengers per city 8 number of passengers per city 27 number of passengers per city 34 number of passengers per city
83.4 59.4 55.6
Source: Airports Council International: Worldwide Airport Traffic Report (1990, 1995, 2000), Geneva. Airports Council International.
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the number of passengers as the beta group. Taken together these tables show there has been change in the distribution of air passengers among cities, with some gains felt in the cities in the third ranked group in particular. The role of the very large airports has not changed significantly however. Given that the approach to data assembly was biased a little in favour of the alpha cities (as seven in the group have multiple airports) this shift is even more significant. 4.2. A passenger hierarchy of cities The research also explored the distribution of passengers between airports arrayed by absolute size, rather than by function or influence. This approach meant that US airports like Atlanta, Miami and Las Vegas that have high passenger numbers are given greater prominence. In addition, toward the bottom end of the list many smaller airports in the US (e.g. Raleigh–Durham), Europe (e.g. Nice) and elsewhere (e.g. Busan and Kaoshiung) are included; these places do not figure in the functional classification developed by the GaWC research group. Their inclusion here might tap the dispersal of activities in parts of manufacturing and tourism associated with globalisation as discussed earlier. For convenience, the top 100 airports listed by the ACI have been broken down into four categories as shown in Table 3. The data in Table 3 confirm the output of the first stage of the research. The share of all passenger move-
Table 3 Share of passengers at the top 100 airports 1990–2000 Rank Top 10 Ranked 11–20 Ranked 21–50 Ranked 51–100
1990
1995
2000
36.3 15.7 25.2 22.8
32.9 15.5 28.1 23.5
31.0 14.9 29.4 24.7
100.0
100.0
100.0
Source: Airports Council International: Worldwide Airport Traffic Report (1990, 1995, 2000), Geneva. Airports Council International.
ment through the top 10 airport cities (six of which are multiple airport cities) has been declining, along with the share recorded in the next group, while the two groups of smaller cities have attracted increased shares of passengers. In fact the passenger traffic through the cities ranked 21–50 is now much closer to that recorded through the top 10, whereas there was a major difference in their shares of traffic just 10 years earlier. Table 4 confirms that the third group of 30 cities has recorded a very substantial increase in passenger movement, although on average cities in that group account for half the growth of the average city in the top 10; average passenger movement at the latter is over three times that recorded at the average third category city. This information confirms that while the very large cities remain prominent in air passenger movement there has been a shift away from the big airport cities, and the gains have been in a third ranked group. 4.3. Measuring travel between airports The measures reviewed above are based on counts of people moving through airports. In the second stage of the research information on the linkage between those airports was used. This involved using connectivity indices calculated by Timberlake et al. (2000) for groups of cities in the GaWC classification, which are displayed in Figs. 1 and 2 and cities in the alpha and beta categories. Because of the large number of cities in the gamma category indices are displayed in Table 5. Fig. 3 shows the indices at different levels in the traffic hierarchy. The index displayed in the graphs has been expressed in a range from 0 to 1000, rather than 0–1. A common element in the diagrams and tables is that connectivity rose for many cities up to 1994, but declined after that date. That is most apparent for the cities in the alpha category other than London. There are some cities that have recorded steady increases in connectivity however. Significantly they are a couple in the beta category (Mexico City and Seoul), those named in the first part of Table 5, and cities ranked at 20, 30, 40
Table 4 Passenger traffic at the top 100 airports 1990–2000 (million passengers) Rank
1990
1995
2000
Change 1995–2000
Percentage change 1990–2000
Top 10 average number of passengers per city 11–20 Average number of passengers per city 21–50 Average number of passengers per city 51–100 Average number of passengers per city
560,213 56,021 241,888 24,188 389,594 12,986 353,386 7067
653,662 65,366 308,743 30,874 558,783 18,626 469,825 9396
811,074 81,107 392,010 39,201 767,412 25,580 646,272 12,925
250,858 25,085 150,122 15,012 377,818 12,593 292,886 5858
44.8 62.0 96.9 82.8
Source: Airports Council International: Worldwide Airport Traffic Report (1990, 1995, 2000), Geneva. Airports Council International.
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Fig. 1. Connectivity indices for alpha global cities 1991–1997. Source: Timberlake et al. (2000).
Fig. 2. Connectivity indices for beta category global cities 1991–1997. Source: Timberlake et al. (2000).
and 50 in the passenger hierarchy. Taken together this information confirms the emphasis of change in the distribution of passenger numbers toward the second and third ranked cities, as the previous analysis had exposed. Smith and Timberlake (2002) have analysed this data in a different way. They use 22 cities drawn mainly from the alpha and beta categories in the GaWC classification. They find that between 1991 and 1994 there is a bunching of the mid-sized cities in their sample around a similar value of the index. That outcome involves San Francisco, Milan, Madrid, Chicago, Amsterdam and Zurich. The bunching weakens a little by 1997. For them the result suggests the simple hierarchical differentiation in the role places play in the global network has begun to weaken. Interpreted in the context of the present paper, that seems consistent with a stronger role of second and third ranked cities as origin and destinations.
5. Implications The shift in traffic detected here is likely to be related to changes in aircraft technology, a gradual deregulation of air travel (induced in part through alliances and assisted by new small carriers) and changes in the production systems of firms in a range of industries. These changes represent another stage in the way globalisation is shaping the cities within the world economy. For transport geography, the information means that analytical frameworks need to look beyond continuation of the role of very large cities and incorporate a greater role for next-sized cities. For airport planning and development, the results imply that pressure to provide additional capacity to manage air passenger numbers might move away from the very large cities to those in the next rank and below. The research also implies that the long term evolution of air travel probably lies in the mid-sized and smaller
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Table 5 Connectivity indices for gamma category cities 1991
1994
1997
Cities recording steady increase in connectivity: 1991–1997 Caracas 186 192 216 Copenhagen 300 347 356 Osaka 154 195 364 Manila 261 285 292 Prague 126 184 195 Santiago 178 235 243 Washington 188 204 252 Cities recording uneven change in connectivity: 1997 level > 1991 level Amsterdam 575 677 614 Boston 189 245 239 Kuala Lumpur 245 242 311 Montreal 152 171 155 Stockholm 241 214 259 Warsaw 181 145 183 Cities recording uneven change in connectivity: 1997 level < 1991 level Bangkok 492 504 444 Budapest 163 47 41 Houston 238 260 202 Jakarta 159 188 122 JoÕburg 200 94 101 Miami 530 575 533 Taipei 287 257 259
aircraft capable of providing links between those cities in the middle and lower levels of the top 100 airports identified here. Perhaps there is less scope than some people have predicted for the extended jumbo that is being planned by Airbus. That observation is consistent with a conclusion of a recent overview of the corporate competition between Boeing and Airbus: Ô. . .most of the competition will continue to be in smaller aircraft’’ (The Economist, 2002b, 73). On another tack, as the pattern of air passenger traffic re-
flects the location and activity of the economy, any greater dispersal of global activity toward cities in the second level in the hierarchy will continue the shift of traffic away from the top ranked global cities. However, it is also important to recognise that a small number of these global cities remain the dominant feature of world aviation. In fact in 2000, the airports in four city-regions, London, New York, Chicago and Tokyo, accounted for 23% of the total passenger movement through the worldÕs 100 busiest airports. The continued role of these big city regions will keep the planning and management of airport infrastructure at the forefront of airport planning in the immediate future. That planning may need to recognise the use of the very large Airbus 380 for hub-to-hub services. At the time of writing it appears that the September 11, 2001 terrorist attack, along with the slowing in the world economy, has changed both the number of people flying and the cities they want to visit. Although too early to analyse in the format outlined above, one response seems to have been a shift away from smaller markets to concentrate traffic on larger centres. As an illustration, Qantas withdrew from many of the routes to smaller Asian and European cities and maintained services on its routes to London and Los Angeles. However, by February 2002 Airline Business (2002, 24) reported that ‘‘middle ranking US airlines have recovered faster’’ but acknowledged that it was too early to say whether this represented a major structural shift in the industry or its operations. This suggests corporate change in the airline industry could emerge as a key influence upon the distribution of passenger numbers. If that change involves large airlines losing market share to smaller companies, there may be a flow-on effect into the geography of passenger movement as the
Fig. 3. Connectivity indices for cities ranked in passenger hierarchy 1991–1997. Source: Timberlake et al. (2000).
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very large airlines all tend to have major city airports as their home base. A diminution in their corporate activity may be felt in a diminution in their traffic and hence passenger movement. On balance then, the research reported here, along with current changes in airline operation, airport management and the distribution of business all seem to point to a continued shift in passenger traffic away from very large cities toward those next in rank.
Acknowledgements The author thanks John Bowen for an invitation to join a panel on Pacific Rim Air and Maritime Transport at the American Association of Geographers where an initial draft of this paper was discussed. Travel funds from the Faculty of Architecture, Building and Planning at the University of Melbourne made it possible to attend the AAG meeting and also to purchase the data used here. Staff in the Research Division of the Airports Council International, Geneva were very helpful in the prompt delivery of the data. In addition thorough reviews by two anonymous referees substantially improved the paper, one in particular suggesting the use of the airport averages used in Tables 2 and 4. Thanks also to the Global and World City Project at Loughborough University for making available a wealth of information, including in particular the David Smith and Michael Timberlake data base on airport connectivity.
Appendix A. The global and world cities classification, with cities included in the analysis Alpha world cities: Chicago, Frankfurt, Hong Kong, London, Los Angeles, Milan, New York, Paris, Tokyo, Singapore. Beta world cities: Brussels, Madrid, Mexico City, Moscow, San Francisco, Sao Paulo, Seoul, Sydney, Toronto, Zurich. Gamma world cities: Amsterdam, Atlanta, Bangkok, Barcelona, Boston, Buenos Aires, Budapest, Copenhagen, Dallas, Dusseldorf, Geneva, Hamburg, Houston, Istanbul, Jakarta, Manila, Melbourne, Miami, Minneapolis, Montreal, Munich, Osaka, Rome, Stockholm, Taipei, Warsaw, Washington. Delta cities: Adelaide, Auckland, Birmingham, Bogota, Bologna, Brazilia, Brisbane, Bucharest, Calgary, Cairo, Colombo, Columbus, Cleveland, Cologne, Detroit, Edinburgh, Glasgow, Gothenburg, Kansas City, Leeds, Lisbon, Manchester, Marseille, Montevideo, Oslo, Richmond, Rotterdam, Riyadh, St. Petersburg, Seattle, Stuttgart, Tijuana, Turin, Vancouver.
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Appendix B. Multiple city airports Chicago: Dallas: Houston:
OÕHare, Midway, Meigs Field. Dallas-Fort Worth, Love Field. George Bush International, WP Hobby. Jakarta: Halim Perdankusuma, Soekarno Hatta. London: Heathrow, Gatwick, Stansted, Luton, City. Los Angeles: LAX, Long Beach, Ontario, Burbank, Santa Barbara, Santa Ana. Las Vegas: Henderson, McCarran, North Las Vegas. Milan: Linate, Malpesa. Montreal: Dorval, Mirabel. Moscow: Shermetyevo, Vnukovo. New York: JFK, Newark, La Guardia, Newburg, White Plains. Osaka: Kansai, Itami. Paris: Charles de Gaulle, Orly. Rome: Ciampino, Fiurmicino. San Francisco: Oakland, San Francisco, San Jose. Tokyo: Narita, Haneda. Washington: Baltimore/Washington, IAD, Washington National.
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