Climate Change Projections and World Agricultural Impact

Introduction

The topic of climatic change is one that is ever present on the minds of scientists and meteorologists, as well as many others across the globe. Since the melting of the earth's northern and southern polar ice caps, reports of massive waves disrupting ocean travel, and news of glacier and ice shelf events, virtually everyone is slowly but surely becoming aware of the changes in the climatic conditions of the earth's biosphere. These changes affect all life on earth — humans, animals, marine life, and organisms alike. Water temperatures, air quality, and every element upon, within, and surrounding the planet will collectively experience the effects of a shifting climate.

Climatologists have now stated that it is within the realm of "certain probability" that humans have induced global climatic disturbances resulting in a fundamental change in current conditions. Furthermore, the projected impact on human health is described as diverse, "unpredictable in magnitude," and slow to emerge. Specifically, it is stated that "adverse effects are likely to outweigh beneficial effects substantially" (McMichaels et al., eds., 2004). However, the changes most likely to be witnessed sooner rather than later are those stemming from difficulties in agricultural production — including crop disasters and mass failures caused by unforeseen disruptions within the earth's biosphere.

Climatologists and Meteorologist Predictions

The predictions are gloomy with regard to the earth's agricultural outlook. Demands for food have risen in recent years, and many people die daily due to starvation in developing countries. More land is being cultivated each year, and researchers note that this places additional pressure on natural ecosystems. Agricultural crop yields are expected to be affected directly through "alterations in temperature and rainfall," as well as indirectly through "changes in soil quality, pests, and diseases." It is specifically stated that cereal yields are expected to decline in India, Africa, and the Middle East (EduGreen Online, 2005).

The World Health Organization and World Meteorological Organization collaborative report further elaborates on these threats:

Agricultural Issues

"The potential impacts of climate change upon agricultural productivity — while temperature increases and soil moisture changes, and shifts in patterns of plant pest and diseases, could lead to decreases in agricultural productivity, carbon dioxide fertilization could lead to some increases in agricultural productivity. But regional variations in gains and losses would probably result in a slight overall decrease in world cereal productivity. Decreases would be most likely in regions that are already food-insecure." (McMichaels et al., eds., 2004)

The World Health Organization also identifies probable changes including "extreme weather events, heatwaves, floods, storms and droughts, and heavy precipitation events leading to increased flooding" (WHO, 2005). Also mentioned as probable are widespread starvation and the incidence of psychological and social disorders. Rising sea levels would result in significant losses of agricultural land and fisheries. Freshwater supplies are expected to become salinized, and storm surges are anticipated to intensify. Additionally, increased exposure to ultraviolet radiation (UVR) is projected to have "adverse effects on biomass production, and hence on human food production, although the magnitude of such effects is uncertain" (McMichaels et al., eds., 2004).

It is also noted that the earth's movement through regions of heightened solar activity has contributed to surges in solar radiation and atmospheric heating, further warming the biosphere. If any good news exists amid these projections, it is that mitigation strategies, if properly and promptly applied, may ease the severity of some of these changes.

The worst-case scenario, as identified in the research literature, involves severe and compounding disruptions to agricultural systems worldwide, including widespread crop failure, loss of arable land to rising seas, and collapse of freshwater availability. Figures 2.0 and 2.1, sourced from the U.S. Global Change Research Information Office, illustrate the contrast between the worst-case and best-case projected outcomes respectively. The best-case scenario assumes timely mitigation efforts and adaptive agricultural practices that could limit the most severe impacts, though even this optimistic outlook anticipates meaningful regional disruptions.