I was struck by this article in the Scotsman today highlighting the drop in passenger numbers at Scotland's two main airports Glasgow and Edinburgh. In January both airports had fewer passengers than in January 2011. However, comparing the year with the previous year passenger numbers were up at both airports.
Several ad hoc reasons were offered by the airport managements for the fall. Interestingly, the drop was in domestic not international passenger numbers.
I thought the change warranted a deeper look. The chart below shows the annual percentage growth in passenger numbers at the two airports.
There is a clear downward trend at both airports. The rate of growth has been falling over the past ten years. It went into negative territory at Glasgow in 2007 and in 2010 at Edinburgh.
I do not know for certain the reason for the decline in passenger growth. I am not an industry expert. There may be a recession effect since 2007. But, my guess is that part of the reason may be the resurrection of rail travel between Scotland and the rest of the UK. See this chart
The chart plots the growth in air and rail travel to/from Scotland and rest of UK with 2000 set as the base. The growth in air journeys between Scotland and the UK peaked in 2005. Rail journeys between Scotland and UK started to grow fairly rapid the year before. This looks like a clear switching of modes. It is probably linked to the improvement in the rail service on the west coast line. And may also be linked to the rising real opportunity cost of air travel as security measures have intensified.
Whatever the reason, the shift looks to be continuing. And one should not forget the probable environmental dividend.