Air travel to contribute more to global warming

by Someshwar Singh

Geneva, June 4 -- Emissions from aircrafts, which are more persistent and damaging than ground-level emissions, will be contributing much more to global warming by the year 2050, according to a new report released here today by the Intergovernmental Panel on Climate Change (IPCC).

The new report, "Aviation and the global atmosphere", was developed over the last two years by a group of more than 100 scientists.

Requested by the International Civil Aviation Organization (ICAO), the report is a joint effort of the IPCC and the Scientific Assessment panel of the Montreal protocol on Substances that Deplete the Ozone Layer.

The report provides a detailed assessment of the impact of all of the gases and particles emitted by aircraft engines on climate and atmospheric ozone.

Air travel is projected to grow by about 5% annually until 2015, burning 3% more fuel per year in that period. Aircraft emissions, and their impacts, will be far greater in 2050 unless new technologies and operational modes are developed, says the report.

Fuel consumption by civil aviation is expected to reach 300 million tonnes in 2015 and 450 million tonnes in 2050, compared to 130 million tonnes in 1992. There will be corresponding high emissions of greenhouse gases such as carbon dioxide and water vapour as well as nitrogen oxides and sulphur oxides.

The report also considers how potential changes in aircraft technology, air transport operations and the institutional, regulatory and economic framework might affect emissions in the future. It describes the state of scientific knowledge together with associated uncertainties.

Releasing the report, Dr. N. Sundararaman, Secretary of the IPCC, said the purpose of the report was purely 'fact-finding' and not to prescribe policy. It was up to governments and others to act upon the findings contained in the report, he added.

Answering questions on what could be done to mitigate the effects on global warming caused by aircrafts, Dr. Sundararaman said improvements in the engine technology were making lower emissions possible, but that was happening for reasons other than environmental concerns.

Operational aspects and changes in traffic controls could also bring considerable reductions in fuel use, he added. For instance, if the stacking of planes upon landing could be avoided, that alone could effect a saving of upto 20% in fuel use in the next 10 years.

Another important area where changes could be brought about was the practice of bunkering - where aircrafts feel obliged to carry more fuel from one location rather than picking it up at the next destination - for reasons of cost.

As for an alternative fuel, Dr. Sundararaman said hydrogen could be an alternative to fossil fuels but that gearing up an entire infrastructure for that would take a lot of time and effort.

"It has taken more than a 100 years for us to come to our present infrasttructure," he said.

However, the report warns that although improvements in aircraft and engine technology and in the efficiency of the air traffic system will bring environmental benefits, these will not fully offset the effects of the increased emissions resulting from the projected growth in aviation.

Policy options to reduce emissions further include more stringent aircraft engine emission regulations, removal of subsidies and incentives that have negative environmental consequences, market- based options such as environmental levies (charges and taxes) and emissions trading, and substitution of aviation by rail and coach.

Most of these options, says the report, would lead to increased airline costs and fares. Some of these approaches have not been fully investigated or tested in aviation and their outcomes are uncertain, it added. (SUNS4449)

The above article first appeared in the South-North Development Monitor (SUNS).