The impact of global warming on food prices and hunger could be large over the next 20 years, according to a new Stanford University study. Researchers say that higher temperatures could significantly reduce yields of wheat, rice and maize - dietary staples for tens of millions of poor people who subsist on less than $1 a day. The resulting crop shortages would likely cause food prices to rise and drive many into poverty.  

But even as some people are hurt, others would be helped out of poverty, says Stanford agricultural scientist David Lobell.

Lobell discussed the results of his research on Feb 19 at the annual meeting of the American Association for the Advancement of Science in San Diego.

"Poverty impacts depend not only on food prices but also on the earnings of the poor," said Lobell, a center fellow at Stanford's Program on Food Security and the Environment (FSE). "Most projections assume that if prices go up, the amount of poverty in the world also will go up, because poor people spend a lot of their money on food. But poor people are pretty diverse. There are those who farm their own land and would actually benefit from higher crop prices, and there are rural wage laborers and people that live in cities who definiztely will be hurt."

Lobell and his colleagues recently conducted the first in-depth study showing how different climate scenarios could affect incomes of farmers and laborers in developing countries.

Household incomes

In the study, Lobell, former FSE researcher Marshall Burke and Purdue University agricultural economist Thomas Hertel focused on 15 developing countries in Asia, Africa and Latin America. Hertel has developed a global trade model that closely tracks the consumption and production of rice, wheat and maize on a country-by-country basis. The model was used to project the effects of climate change on agriculture within 20 years and the resulting impact on prices and poverty.

Using a range of global warming forecasts, the researchers were able to project three different crop-yield scenarios by 2030:

• "Low-yield" - crop production is toward the low end of expectations.
• "Most likely" - projected yields are consistent with expectations.
• "High-yield" - production is higher than expected.

"One of the limitations of previous forecasts is that they don't consider the full range of uncertainties - that is, the chance that things could be better or worse than we expect," Lobell said. "We provided Tom those three scenarios of what climate change could mean for agricultural productivity. Then he used the trade model to project how each scenario would affect prices and poverty over the next 20 years.

"The impacts we're talking about are mainly driven by warmer temperatures, which dry up the soil, speed up crop development and shut down biological processes, like photosynthesis, that plants rely on," he added. "Plants in general don't like it hotter, and in many climate forecasts, the temperatures projected for 2030 would be outside the range that crops prefer."

Results

The study revealed a surprising mix of winners and losers depending on the projected global temperature. The "most likely" scenario projected by the International Panel on Climate Change is that global temperatures will rise 1.8 degrees Fahrenheit (1 degree Celsius) by 2030. In that scenario, the trade model projected relatively little change in crop yields, food prices and poverty rates

But under the "low-yield" scenario, in which temperatures increase by 2.7 F (1.5 C), the model projects a 10 to 20 percent drop in agricultural productivity, which results in a 10 to 60 percent rise in the price of rice, wheat and maize. Because of these higher prices, the overall poverty rate in the 15 countries surveyed was expected to rise by 3 percent.

However, an analysis of individual countries revealed a far more complicated picture. In 11 of the 15 countries, poor people who owned their own land and raised their own crops actually benefited from higher food prices, according to the model. In Thailand, for example, the poverty rate for people in the non-agricultural sector was projected to rise 5 percent, while the rate for self-employed farmers dropped more than 30 percent - in part because, as food supplies dwindled, the global demand for higher-priced crops increased.

"If prices go up and you're tied to international markets, you could be lifted out of poverty quite considerably," Lobell explained. "But there are a lot of countries, like Bangladesh, where poor people are either in urban areas or in rural areas but don't own their own land. Countries like that could be hurt quite a lot. Then there are semi-arid countries - like Zambia, Mozambique and Malawi - where even if prices go up and people own land, productivity will go down so much that it can't make up for those price increases. In the 'low-yield' scenario, those countries would see higher poverty rates across all sectors."

Under the "high-yield" scenario, in which global temperatures rise just 0.9 F (0.5 C), crop productivity increased. The resulting food surplus led to a 16 percent drop in prices, which could be detrimental to farm owners. In Thailand, the poverty rate among self-employed farmers was projected to rise 60 percent, while those in the non-agriculture sector saw a slight drop in poverty. In Zambia, Mozambique, Malawi and Uganda, poverty in the non-farming sector was projected to decline as much as 5 percent.

Risk management

Lobell said that, although the likelihood of the "low-yield" or "high-yield" scenario occurring is only 5 percent, it is important for policymakers to consider the full range of possibilities if they want to help countries adapt to climate change and ultimately prevent an increase in poverty and hunger. 

"It's like any sort of risk management or insurance program," he said. "You have to have some idea of the probability of events that have a big consequence. It's also important to keep in mind that any change, no matter how extreme, will benefit some households and hurt others."

The Program on Food Security and the Environment at Stanford is an interdisciplinary research and teaching program that generates policy solutions to the persistent problems of global hunger and environmental damage from agricultural practices worldwide. The program is jointly run by Stanford's Woods Institute for the Environment and the Freeman Spogli Institute for International Studies.

In December 2009, the Asia Health Policy Program celebrates the first anniversary of the launch of the AHPP working paper series on health and demographic change in the Asia-Pacific. The series showcases research by AHPP’s own affiliated faculty, postdoctoral fellows, and visiting scholars, as well as selected works by other scholars from the region.

To date AHPP has released eleven research papers in the series, by authors from China, South Korea, Thailand, Taiwan, Pakistan, and the US, with more on the way from Japan and Vietnam. Topics range from “The Effect of Informal Caregiving on Labor Market Outcomes in South Korea” and “Comparing Public and Private Hospitals in China,” to “Pandemic Influenza and the Globalization of Public Health.”  The working papers are available at the Asia Health Policy website.

AHPP considers quality research papers from leading research universities and think tanks across the Asia-Pacific region for inclusion in the working paper series. If interested, please contact Karen Eggleston.

Global health disparities were the topic of a special event November 11th co-sponsored by the Asia Health Policy Program of the Shorenstein Asia-Pacific Research Center and the Center for Health Policy / Primary Care and Outcomes Research.

Sir Michael Marmot, internationally renowned Principal Investigator of the Whitehall Studies of British civil servants (investigating explanations for the striking inverse social gradient in morbidity and mortality), spoke about research on the social determinants of health and taking action to promote policy change. Pointing out the extreme disparities in life expectancy for peoples in different parts of the world – including the “haves” and “have-nots” within the high-income world – he presented an overview of “Closing the gap in a generation: Health equity through action on the social determinants of health” (http://www.who.int/social_determinants/en/). That report was commissioned by the World Health Organization (WHO) and released last year; Sir Marmot served as the Chair of the Commission on Social Determinants of Health.

Criticizing those who justify initiatives in global health solely on economic grounds, Sir Marmot argued that addressing the social determinants of health is a matter of social justice.

He presented data and discussed the report’s three primary recommendations: 1. Improve daily living conditions; 2. Tackle the inequitable distribution of power, money, and resources; and 3. Measure and understand the problem and assess the impact of action.
Stating that the World Health Assembly resolution on the social determinants of health was only meaningful as a first “baby step,” Marmot urged the audience to consider how research and policy advocacy can address the social determinants of health so that all individuals can lead flourishing lives.

Examples from Asia include

• the high risk of maternal mortality (1 in 8) in Afghanistan;
• the steep gradient in under-5 mortality in India (with the rate almost three times higher for the poorest quintile than for the wealthiest quintile);
• less than half of women in Bangladesh have a say in decision-making about their own health care;
• a large share of the world’s population living on less than US$2 a day reside in Asia;
• social protection systems like pensions are possible in lower and middle-income countries, with Thailand as an example;
• more can be done to address the millions impoverished by catastrophic health expenditures, such as in southeast Asia; and
• conflict-ridden areas and internally displaced people, such as in Pakistan and Myanmar, are among the most vulnerable.

He also responded to questions about the role of freedom and liberty in social development – contrasting India and China – and commented on the peculiar contours of the US health reform debate.

Professor Marmot closed by noting that, in exhorting everyone to strive for social justice and close the gaps in health inequalities all too apparent in our 21st century world, he hoped he was not too much like Don Quixote, going around “doing good deeds but with people all laughing at him.” 
Professor Sir Michael Marmot MBBS, MPH, PhD, FRCP, FFPHM, FMedSci, is Director of the International Institute for Society and Health and MRC Research Professor of Epidemiology and Public Health at University College, London. In 2000 he was knighted by Her Majesty The Queen for services to Epidemiology and understanding health inequalities.

How do countries in the vast and diverse Asia-Pacific region differ in “prescribing cultures”? How do health systems in the region balance access to pharmaceuticals with incentives for innovation? How do the forces of globalization shape, and in turn are shaped by, cultural legacies about health and health care? These are the key questions addressed by the new Asia Health Policy Program book, Prescribing Cultures and Pharmaceutical Policy in the Asia Pacific.

AHPP held a book launch event September 23rd with three authors of the book detailing how pharmaceutical policies are interlinked globally and at the same time deeply rooted in local culture.