New Zealand Celsias

A new study by a team of international scientists   and led by a NASA climate scientist reports that inexpensive and relatively simple measures to cut two key pollutants could dramatically slow global warming, improve health, and boost crop production worldwide.

For years climate-change efforts have focused on reducing carbon dioxide (CO2), the result of fossil fuel and biomass burning.  Cutting CO2 emissions is challenging; the gas traps heat and remains in the atmosphere for decades.  The new research, led by Drew Shindell of NASA’s Goddard Institute for Space Studies (GISS)   in New York City, finds that reducing two shorter-term pollutants–methane and soot—could slow global warming 0.9 ºFahrenheit by 2050, increased global crop yields by up to 135 metric tons per season, and prevent hundreds of thousands of premature deaths each year.  The study, published in the journal,Science  , focused on 14 measures that would create the greatest climate benefit.  All of the measures would diminish the release of either soot or methane.

Says Shindall in a NASA news release  , “We’ve shown that implementing specific practical emissions reductions chosen to maximize climate benefits also would have important ‘win-win’ benefits for human health and agriculture.”

Soot—otherwise known as black carbon—is a product of the incomplete burning of wood, dung, coal and other fuels and cause or increase respiratory and cardiovascular problems.  Soot’s small particles absorb radiation from the sun, causing the atmosphere to warm and rainfall patterns to shift, adding to global warming. 

Methane is a colorless, flammable component of natural gas similar to CO2 that reacts with other gases to form ground-level ozone.  Ozone is a major greenhouse gas that damages human health as well as crops.  Unlike CO2, both methane and soot circulate out of the atmosphere relatively quickly. 

According to the study, among the 14 measures that would reduce methane include:

• Capturing gas that escapes from coal mines and oil and natural gas facilities
• Updating wastewater treatment plants
• Stopping emissions from city landfills
• Draining rice paddies more often
• Reducing emissions from manure on farms.

Measures to reduce soot in the atmosphere include:

• Keeping the worst-polluting vehicles off the road
• Upgrading family cook stoves with cleaner-burning types
• Building more efficient kilns for brick making and upgrading coke ovens
• Banning agricultural burning

Shindall’s team of researchers concluded that these control measures that some regions would benefit more than others from these measures.  Regions with large areas of snow and ice cover such as Russian, Tajikistan, and Kyrgyzstan would see less warming, while Pakistan, Iran, and Jordan would see the greatest gains in agricultural production.  The countries of Bangladesh, Nepal, and India would experience the greatest reductions in premature deaths.

The scientists used computer models created at GISS   and the Max Planck Institute for Meteorology in Hamburg, Germany   to develop models that show the impact of emissions reductions. The study was a follow-up to a report by the United Nations Environment Program/World Meteorological Organization   released last year, also led by Shindell.