Featured Research

from universities, journals, and other organizations

Reducing Air Pollution Could Increase Rice Harvests In India

Date:
December 9, 2006
Source:
University of California - Berkeley
Summary:
An analysis by researchers at UC Berkeley and UC San Diego found that the combined effects of atmospheric brown clouds and greenhouse gases negatively affected growing conditions for rice in India. The researchers estimate that harvests would have been 20 to 25 percent higher during some years in the 1990s if the negative climate impacts had not occurred. The study suggests that reducing the man-made sources of pollution could increase harvest growth.

In this image, taken Feb. 5, 2006, by NASA's Aqua satellite, a pale band of haze covers northern India, just south of the Himalaya. Haze also intrudes into the skies of southern Nepal and Bangladesh. A study by UC researchers suggests that reducing air pollution could increase rice harvests in India.
Credit: Image Jeff Schmaltz/Moderate Resolution Imaging Spectroradiometer Land Rapid Response Team, NASA Goddard Space Flight Center

New research from the University of California indicates that reductions of human-generated air pollution could create unexpected agricultural benefits in one of the world's poorest regions. These new findings will be published online the week of Dec. 4 in the journal Proceedings of the National Academy of Sciences (PNAS).

Rice harvests increased dramatically in India during the "Green Revolution" of the 1960s and 1970s, making the country self-sufficient in its staple food. Harvest growth has slowed since the mid-1980s, however, raising concerns that food shortages could recur in this densely populated and poor nation. Several explanations for the slowdown have been proposed, but until now, none took into account the complex interactions of two pollution-related sources of climate change: atmospheric brown clouds (ABCs), which form from soot and other fine particles in the air (collectively termed aerosols), and the better-known problem of global warming caused by greenhouse gases such as carbon dioxide.

In the PNAS paper, Maximilian Auffhammer at UC Berkeley's College of Natural Resources, and V. "Ram" Ramanathan and Jeffrey Vincent, researchers at UC San Diego, analyze historical data on Indian rice harvests and examine the combined effects of atmospheric brown clouds and greenhouse gases on growing conditions. They find that the combined effects were negative and were greater after the mid-1980s than before, coinciding with the observed slowdown in harvest growth. They estimate that harvests would have been 20 to 25 percent higher during some years in the 1990s if the negative climate impacts had not occurred.

Previous research by an international scientific team led by Ramanathan, professor of atmospheric sciences at Scripps Institution of Oceanography, found that brown clouds have made the Indian subcontinent drier and cooler. Although this suggests the existence of a climatic tradeoff, with reductions in aerosols potentially unleashing a stronger warming trend, the current study indicates that joint reductions in the two types of pollutants would, in fact, benefit Indian rice farmers. This is because reductions in aerosols would enhance rainfall, while reductions in greenhouse gases would reduce the higher nighttime temperatures that can negatively affect the growth of the rice plant.

"Greenhouse gases and aerosols in brown clouds are known to be competing factors in global warming," said Ramanathan. "The major finding of this interdisciplinary study is that their effects on rice production are additive, which is clearly an unwelcome surprise."

Peter Timmer, senior fellow at the Center for Global Development, an independent, non-profit think tank in Washington, D.C., added that the study "links a sophisticated model of agricultural production in India to climate and pollution models, with the critical finding that 'brown cloud' pollution has already cost India millions of tons of food production."

The researchers noted that the impact of ABCs and greenhouse gases on agriculture provides another incentive for controlling air pollution in heavily polluted Asia. "Air pollution control measures in India have been motivated mainly by concern about the health of residents of the urban areas where most of the pollution is generated," said Vincent, an economist and environmental research director at the UC Institute on Global Conflict and Cooperation (IGCC). "Our study provides an additional motivation related to the economic health of poor rural areas."

Auffhammer, UC Berkeley assistant professor of agricultural and resource economics, added that "while this study focuses on India's rain-fed states, ABCs exist throughout Asia's main rice-producing countries, many of which have experienced decreasing growth rates in harvests, too. Furthering our understanding of how air pollution affects agricultural output is very important to ensure food security in the world's most populous region."

The paper is the result of a three-year collaboration between Auffhammer, Ramanathan and Vincent. Their work was supported in part by the Giannini Foundation, the National Science Foundation, the National Oceanic and Atmospheric Administration and IGCC.


Story Source:

The above story is based on materials provided by University of California - Berkeley. Note: Materials may be edited for content and length.


Cite This Page:

University of California - Berkeley. "Reducing Air Pollution Could Increase Rice Harvests In India." ScienceDaily. ScienceDaily, 9 December 2006. <www.sciencedaily.com/releases/2006/12/061206095357.htm>.
University of California - Berkeley. (2006, December 9). Reducing Air Pollution Could Increase Rice Harvests In India. ScienceDaily. Retrieved July 31, 2014 from www.sciencedaily.com/releases/2006/12/061206095357.htm
University of California - Berkeley. "Reducing Air Pollution Could Increase Rice Harvests In India." ScienceDaily. www.sciencedaily.com/releases/2006/12/061206095357.htm (accessed July 31, 2014).

Share This




More Earth & Climate News

Thursday, July 31, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Visitors Feel Part of the Pack at Wolf Preserve

Visitors Feel Part of the Pack at Wolf Preserve

AP (July 31, 2014) Seacrest Wolf Preserve on the northern Florida panhandle allows more than 10,000 visitors each year to get up close and personal with Arctic and British Columbian Wolves. (July 31) Video provided by AP
Powered by NewsLook.com
Florida Panther Rebound Upsets Ranchers

Florida Panther Rebound Upsets Ranchers

AP (July 31, 2014) With Florida's panther population rebounding, some ranchers complain the protected predators are once again killing their calves. (July 31) Video provided by AP
Powered by NewsLook.com
Big Waves In Arctic Ocean Threaten Polar Ice

Big Waves In Arctic Ocean Threaten Polar Ice

Newsy (July 30, 2014) Big waves in parts of the Arctic Ocean are unprecedented, mainly because they used to be covered in ice. Video provided by Newsy
Powered by NewsLook.com
Raw: Thousands Flocking to German Crop Circle

Raw: Thousands Flocking to German Crop Circle

AP (July 30, 2014) Thousands of people are trekking to a Bavarian farmer's field to check out a mysterious set of crop circles. (July 30) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins