The Assessment, released on May 23 last by the United Nations Environment Program (UNEP) and the Climate and Clean Air Coalition (CCAC), found that poor air quality and global warming is already affecting vulnerable populations and ecosystems in the region resulting in premature deaths, crop yield losses, and ecosystem damage.
In 2010 an estimated 64,000 people died prematurely in the LAC region from exposure to fine air polluting particulate matter (PM2.5) and ground level (tropospheric) ozone. Ozone was also responsible for an estimated 7.4 million tonnes in yield losses of soybean, maize, wheat, and rice. If no action is taken to improve air quality, by 2050, annual premature mortality from PM2.5 and ozone exposure is expected to almost double while annual crop losses could rise to about 9 million tonnes.
The assessment focuses on four short-lived climate pollutants (SLCPs): black carbon (soot), methane, tropospheric ozone, and hydrofluorocarbons (HFCs, typically used in refrigeration and air conditioning). SLCPs are present in the atmosphere for a short period of time compared to carbon dioxide (CO2) – days to decades compared to hundreds of years – and are many times more potent in terms of warming the atmosphere. Black carbon and tropospheric ozone, are also powerful air pollutants that harm human health and the environment.
A number of SLCP reduction measures have been identified that could reduce warming in the LAC region by between 0.3 to 0.9 degrees Celsius by 2050. Over the same timeframe, these measures will decrease annual premature deaths from PM2.5 by at least 25% and deaths from ozone by 40%, and avoid annual losses of 3-4 million tonnes of four major crops – soybeans, maize, wheat, and rice.
The LAC region is one of the most urbanized in the world, with almost 80 per cent living in cities.
The Assessment identifies activities that can significantly reduce SLCP emissions. For example black carbon emissions can be reduced by over 80 per cent by 2050 in most countries by focusing on initiatives that modernize cooking and heating stoves, improve diesel vehicle standards to Euro VI equivalent, put diesel particulate filters on vehicles, eliminate high emitting vehicles, and enforce bans on open field agricultural burning.