Simon Jessop, David Shepardson

GLASGOW (Reuters), – On Wednesday, automakers, governments, and airlines unveiled a slew of promises at the U.N. Climate Summit to reduce greenhouse gas emissions in global transportation. However, there were some notable absences.

Driving, flying and shipping contribute nearly a quarter of the world’s manmade greenhouse gas emissions, making transport a valuable target in the effort to fight climate change.

General Motors and Ford, the U.S. automakers, joined a group committed to eliminating fossil fuel vehicles by 2040. This would accelerate a transition towards electric motors instead of internal combustion engines they invented over 100 years ago. India, the world’s second-largest country, joined the pledge.

In a clear sign of how difficult it is to shift to zero-emissions, two of the top car companies in the world have merged. Toyota Motor (NYSE 🙂 Corp and Volkswagen AG, (OTC 🙂 didn’t sign up. China, America, and Germany did not sign up, as well, for all the major car markets.

Greenpeace Germany representative Martin Kaiser said that it was very concerning to see the main economies and major producers absent. Although the European Union Executive proposed in July to all 27 Member States, which included Germany, that they stop selling combustion vehicles after 2035, it has still not been signed off.

Major U.S. airlines have joined forces in an effort speed up the development and usage of so-called sustainable aircraft fuels (SAF), to lower emissions.

It is produced from renewable resources such as used cooking oil, plants, and other oils. However, it is much more costly than conventional petroleum-based fuel and is not readily available in large amounts.

Alaska Airlines, JetBlue and United Airlines are just a few of the many companies that have joined the initiative to increase SAF production and reduce costs.

According to an International Air Transport Association global commitment, Tuesday’s statement by the United States stated that they are aiming for net-zero emissions of greenhouse gases from their aviation sector by 2050.

Willie Walsh is the director general of IATA. He stated that airlines will achieve an interim goal, which was to use 5.2% sustainable fuel, by 2030 provided they increase their output.

Nearly 3% of all global emissions are caused by air travel, according to researchers. Researchers believe that this figure will rise as the demand for flight increases.

Environmental groups expressed concerns that possible emissions reductions from sustainable aviation fuels were overstated and they have been asking for steps to reduce travel, or zero emission technology for airplanes. This is currently not a realistic prospect.

Around 80% world’s trade is done by sea. Shipment also makes up about 3% worldwide emissions.

The United States and 19 other countries, including Britain, announced that they have agreed to create half a dozen green shipping corridors with zero emission by 2050.

Although the declaration didn’t specify the method, it stated only that the industry would benefit from partnerships with ports and operators in order to decarbonize the sector as well as its fuel supply.