Asia > Asia Climate change is threatening food production

Asia: Asia Climate change is threatening food production

2012/08/13

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Asia Climate change is threatening food production

Climate change is threatening food production systems and therefore the livelihoods and food security of billions of people who depend on agriculture in the Asia and Pacific region (hereafter, Asia and the Pacific). Agriculture is the sector most vulnerable to climate change due to its high dependence on climate and weather and because people involved in agriculture tend to be poorer compared with urban residents.

Consistent warming trends and more frequent and intense extreme weather events have been observed across Asia and the Pacific in recent decades. In line with these trends, climate change scenarios consistently project temperature increases across the region, which will require farmers to adapt to changing conditions.

At the same time, agricultural activities release significant amounts of greenhouse gases (GHG) into the atmosphere. Asia and the Pacific accounts for 37% of the world’s total emissions from agricultural production, and the People’s Republic of China (PRC) alone accounts for more than 18% of the total.
The combination of these characteristics of agriculture—its importance as an economic sector, its vulnerability to climate change, and its contribution to emissions—make building resilience to climate change in Asia and the Pacific an enormous challenge. For the sector to meet the food and income needs of current and future generations, individual farmers, governments, community groups, and the private sector will need to implement comprehensive mitigation and adaptation strategies, which will require targeted investments.


Climate change is expected to have multifaceted impacts on the countries of Asia and the Pacific. Overall, the region is expected to become warmer, with a large degree of variability, depending on latitude. In general, northern areas will experience greater warming than those at lower latitudes.

While the Pacific countries will experience low mean annual changes in rainfall and temperature, rising sea levels are expected to alter significantly not only livelihoods but also livability on some of the smaller islands. Coastal areas in South and Southeast Asia and parts of the PRC will face the triple threat of changing precipitation, temperature, and rising sea levels. Finally, the cooler (northern) subregions of the Asian land mass are expected to get warm, which may lengthen agricultural growing seasons.


The combination of poverty in rural areas and the expected impacts of climate change and its remaining uncertainty will require careful planning for adaptation. Targeted climate change investments and more flexible decision making will be necessary to make the most of scarce budgetary resources, which must also be allocated to crucial social development needs.

A warmer and mostly wetter rainy season, and possibly drier dry seasons Climate change is already evident in a number of ways. Consistent warming trends and more frequent and intense extreme weather events have been observed across Asia and the Pacific in recent decades.


All subregions of Asia and the Pacific are expected to become warmer. While there is less certainty regarding changes in precipitation, Asia and the Pacific are expected generally to get wetter, with the exception of Central Asia. However, rainfall tends to be heavier during wet periods, increasing the risk of floods, while dry seasons will remain dry or get drier. Moreover, the region is expected to experience an increased frequency of extreme weather  events.


The PRC and Viet Nam are the two countries most affected by sea-level rise in terms of total crop land area, followed by Bangladesh, India, and Indonesia. This is based on the results of the International Food Policy Research Institute (IFPRI) Spatial Allocation Model that excludes 12 countries in the Pacific due to unavailable data. Moreover, glaciers in the Himalayas and Central Asia are already melting as a result of climate change. This brings about potential short-term benefits from increased water flows, as well as increased risks from flooding. In the long-term, impacts on food production and ecosystem health will be negative, particularly during the dry season. Much less is known regarding future changes in extreme weather events. Our knowledge regarding the impact of pests and diseases is also insufficient. Given our limited understanding of the nature and extent of impact of climate change on the sector, planning appropriate adaptation and mitigation measures will be carried out under a scenario of uncertainty.

Impact on agriculture

Developing countries in Asia and the Pacific are likely to face the highest reductions in agricultural potential in the world due to climate change. As a result, climate change will place an additional burden on efforts to meet long-term development goals in Asia and the Pacific. Slow agricultural productivity growth, declining income growth, and problems of maintaining food security already pose challenges to many countries in the region.

Modeling climate change impacts on agriculture

For Asia and the Pacific, depending on the General Circulation Model (GCM) and scenario used, biophysical crop model results show yield reductions under climate change compared to a no-climate change scenario. By 2050, for irrigated paddy, the expected reduction is in the range of 14%–20%; for irrigated wheat, 32%–44%; irrigated maize, 2%–5%; and irrigated soybean, 9%–18%. Spreads across crops and GCM are somewhat wider for rainfed crops, with positive yield effects under some GCM, especially in more temperate areas. If carbon fertilization is modeled, then changes in crop yields are much smaller or even turn positive. However, recent research experiments indicate that carbon fertilization effects have been overestimated, and models have yet to be adjusted to account for recent insights.

Incorporating spatially distributed area and yield impacts into the International Model for Policy Analysis on Agricultural Commodities and Trade (IMPACT, developed by the IFPRI) accounts for the autonomous adaptation effects from supply and demand response adjustments as a result of changes in food prices. Changes in the volume and direction of international trade in agricultural commodities are another avenue to compensate for the differential impacts of climate change, and are also taken into account in IMPACT.

When biophysical impacts of climate change are integrated into the IMPACT model, food prices increase sharply for key crops with adverse consequences for the poor. Rice prices are projected to be 29%–37% higher in 2050 compared to a no-climate change case, wheat prices to be 81%–102% higher, maize prices to rise 58%–97%, and soybean prices to increase 14%–49%. Higher food prices lead to declines in total demand for cereal and other crops and a reduction in calorie availability across all Asian subregions, by 13%–15%, on average. The subregion hardest hit is Central Asia, with projected declines in calorie availability of 15% to 18%, given their combination of low levels of calories at the outset and the strong impact from climate change. Childhood malnutrition levels, which are directly linked to calorie availability, are projected to increase dramatically under climate change by between 9 and 11 million children, in addition to the 65 million children projected to remain malnourished in 2050 even under current climate conditions. Avoiding such an increase is difficult but not impossible.

The study implemented several alternative investment scenarios to explore which sectoral investments could help lower future increases in childhood malnutrition for Asia and the Pacific. It found that aggressive investments into agricultural productivity enhancements are the key to reversing climate change impacts on both agriculture and food security—potentially reducing two-thirds of the increase in malnutrition levels arising from climate change. Further reductions could be achieved by more aggressive investments in complementary sectors, such as education, and health. While the strongest climate change reduction results can be achieved from local productivity increases, further trade liberalization, accelerated investments in agriculture in the rest of the developing world as well as by industrialized countries can also provide some relief for Asia and the Pacific.

Climate change will also affect crops and fisheries in the Pacific Island countries, with potential negative consequences for food security. However, the study suffered from a lack of data and additional research will be needed to obtain more specific results for these countries.

Net trade in meats and cereals in Asia will see strong adjustments due to climate change. Under the no-climate change case, only Central Asia will increase its net cereal exports to 2050, while the other subregions of Asia and the Pacific will rely on increasing net imports of cereals. Net cereal imports are projected to increase in East Asia and South Asia under all climate change scenarios. In Southeast Asia, the impact of climate change on trade varies according to the GCM applied. The final trade results produced by the study are the outcome of a complex interaction between the size of the biophysical impact, the resulting price increases, and the responsiveness of demand and supply to prices in each subregion.

Moreover, a warmer and drier climate and more frequent and intense extreme weather events will reduce the agricultural GDP of all countries in Asia, particularly in South and Southeast Asia. Economic losses in the Pacific Island countries are also likely to be high. Fundamentally, across all Asia and the Pacific subregions, but particularly in South and Southeast Asia, climate change will lead to the reduction of agricultural GDP and worsening trade conditions, which will likely increase poverty.

As a result of uncertain climate predictions and other factors (e.g., CO2 fertilization effects, socioeconomic pathways, as well as the individual adaptive capacity of countries), projections of the impacts of climate change on agriculture are not as precise as desired and depend heavily on scenario assumptions. Nonetheless, projections show that agriculture systems in many vulnerable subregions in Asia and the Pacific will suffer with climate change, particularly in South Asia. Further research should be done to better assess detailed impacts in Central Asia and the Pacific Islands.

Resilience as the Conceptual Framework

Resilience is used to describe the magnitude of a disturbance that a system can withstand environmental change or social, economic, or political upheaval, while for natural systems, it is a measure of how much disturbance (e.g., storms, fire, and pollutants) an ecosystem can handle without shifting into a qualitatively different state. This definition implies that social systems have the additional ability to anticipate and plan according to perceived and real changes. Therefore, the ability of institutions and individuals to avoid potential damage and to take advantage of opportunities will be a critical factor in building resilience to climate change. In addition, building resilience to climate change requires simultaneously building resilience in human systems and in the interlinked ecosystems on which they depend.

The concept of resilience has emerged in response to the need to manage interactions between human systems and ecosystems sustainably. Humans depend on ecosystem services (e.g., water filtration, carbon sequestration, and soil formation) for survival, yet the ability of institutions to manage these natural systems sustainably has not kept pace with the changes occurring within these systems. Socioeconomic institutions have considered ecosystems and the services they provide to be infinite and largely in a steady cycle of regeneration. This attitude has led to the creation of economic instruments and incentives that use ecosystems deterministically, from extraction to consumption. The concept of resilience, however, recognizes that social and environmental systems are interlinked, complex, and adaptive; process dependent—rather than input dependent—and selforganizing rather than predictable. The lens of resilience is useful in analyzing climate change because it is founded on the recognition that human existence within ecological systems is complex, unpredictable, and dynamic, and that institutional measures and responses should be based on this principle.

Agriculture is a form of natural resource management for the production of food, fuel, and fiber. As such, it depends on the resilience of both social and ecological systems. In social systems, resilience varies greatly among households, communities, and regions, depending both on the assets and knowledge farmers can mobilize and the services provided by governments and institutions. On the other hand, the resilience of agriculturerelated ecosystems depends largely on slowly changing variables, such as climate, land use, nutrient availability, and the size of the farming system. In addition, agriculture is a source of livelihood for billions of people—particularly poor people—and their income directly contributes to society’s resilience. As a result, enacting measures to build agricultural resilience requires an understanding of strategies to reduce vulnerability while at the same time generating income and reducing poverty.

Vulnerability to climate change in  Asia and the Pacific

The Intergovernmental Panel on Climate Change (IPCC) defines vulnerability as a function of the character, magnitude, and rate of climate variation to which a system is exposed; its sensitivity; and its adaptive capacity. More succinctly, vulnerability is defined as having three components: exposure, sensitivity, and adaptive capacity.
Exposure has been used in the literature to characterize the biophysical impacts of climate change on agroecological systems. Exposure encompasses the spatial and temporal dimensions of climate variability, such as droughts and heavy rains, the magnitude and duration of weather events, and long-term change in mean climate (temperature and precipitation).

Vulnerability to climate change depends not only on exposure to climate events, but also on physical, environmental, socioeconomic, and political factors that influence how sensitive countries will be to a changing climate, as well as their ability to cope and to adapt. For adaptation and mitigation measures to be successful, an assessment of poor communities’ current vulnerabilities, needs, and coping abilities is needed, including influential factors such as gender equality.

Sensitivity is defined by the IPCC as “the degree to which a system is affected, either adversely or beneficially, by climate variability or change” and refers to the ability of an agroecological system to withstand impacts without overt efforts to adapt. Sensitivity is a complex concept because the responsiveness of a system can be influenced by both intrinsic characteristics and degrees of external manipulation. For example, unprotected low-lying coastal areas may be more sensitive to rising sea levels and storm surges than those that have sea walls. Similarly, water-stressed areas that have no irrigation infrastructure will be more sensitive to drought compared to those that do have such systems in place. In Asia and the Pacific, many countries are sensitive to climate change and extreme weather events because of high water stress, high rates of land degradation, and the high dependency of their economies on agriculture.

Low-income and other vulnerable populations will feel the effects of climate change and increases in the incidence of natural disasters most strongly. For instance, climate change is likely to increase the vulnerability of poor farmers who already struggle with land degradation in Asia and the Pacific. In areas highly dependent on livestock production, such as Mongolia and Inner Mongolia, the PRC, overgrazing increases vulnerability to climate change. without crossing a threshold into a new structure or dynamic. In human systems, resilience refers to the ability of communities to withstand and recover from stress, such as Rural women from developing countries will be among the most affected groups in the world given their dependence on subsistence crops, their limited access to resources, and their lack of decision- making power. Adaptation strategies should acknowledge the greater vulnerability of women to climate change.

Health impacts in developing countries are expected to be mostly negative. The ultimate impacts of climate change will be highly dependent on the capacity of countries to limit disease transmission and treat infections. Climate change might increase the global burden of disease as more frequent and severe floods and droughts, as well as changes in mean temperatures and rainfall are likely to increase the number of people at risk.

A combination of indicator values representing exposure (change in temperature and precipitation), sensitivity (share of labor in agriculture), and adaptive capacity (poverty) identifies Afghanistan, Bangladesh, Cambodia, India, Lao PDR, Myanmar, and Nepal as the countries most vulnerable to climate change in Asia and the Pacific. Countries with significant vulnerability—poor outcomes in two out of the above three components— include Bhutan, the PRC, Indonesia, Pakistan, Papua New Guinea, Sri Lanka, Thailand, Timor-Leste, Uzbekistan, and Viet Nam. As in Africa, those countries least responsible for climate change are likely to suffer most from its adverse impacts as a result of their location and low adaptive capacities. On the positive side, however—as has been shown by improvements in Bangladesh’s ability to withstand tropical cyclones—adaptation is possible even for the most destitute and vulnerable countries.

The Role of Adaptation

Important ongoing development initiatives need to be strengthened to reduce vulnerability to climate change, including developing agricultural markets, reducing distortions and subsidies in agricultural policies, continuing trade liberalization policies, enhancing social protection and microfinance, preparing for disasters and, critically, mainstreaming climate change in agricultural policies. However, neither these development policies, nor autonomous or reactive adaptation, will be enough for countries of Asia and the Pacific to adapt to climate change.

Instead, adaptation will require improvements that take existing development policies above and beyond their current capacity. Innovative policies include:

  • (i) changing investment allocation within and across sectors,
  • (ii) increasing the focus on risk-sharing and risk-reducing investments,
  • iii) improving spatial targeting of investments,
  • (iv) eliminating existing detrimental policies that will exacerbate climate change impacts,
  • (v) reducing greenhouse gas (GHG) emissions from agriculture and increasing the value of sustainable farming practices through the valuation of carbon and other forms of agricultural ecosystem services such as water purification and biodiversity.

Key components of new and innovative adaptation measures to climate change include

  • (i) changes in agricultural practices to improve soil fertility and enhance carbon sequestration;
  • (ii) changes in agricultural water management for more efficient water use;
  • (iii) agricultural diversification toward enhanced climate resilience;
  • (iv) agricultural science and technology development, agricultural advisory services, and information systems;
  • (v) risk management and crop insurance.
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