Climate Factors Affecting Soil Erosion

Rain and Snow

• Roughly 15 percent of Earth's bare surface suffers from some degree of deterioration. As of 2011, water erosion accounts for about 65 percent of this damage, while wind erosion comes in second at roughly 28 percent, according the Global Assessment of Soil Deterioration (GLASOD). Heavy seasonal rains wash away unprotected soil, especially in sloping areas, while melting winter snow adds to rainfall amounts, particularly during the spring months in the northern hemisphere. Sandy and silty soils are particularly vulnerable because of their looseness and lack of reinforcement, such as vegetation, that holds heavier soil in place. Erosion occurs at different rates based on the severity of weather events, from the slow movement of soil during many small rainfalls to highly visible damage such as deep gullies caused by larger, more powerful storms.

Wind

• High winds blow away lighter, drier soils, causing uneven terrain and topsoil loss. Well-anchored soil held in place by tree roots, grass and other vegetation is less likely to suffer from wind erosion. Dust clouds are seen in affected areas, as is soil that accumulates in drifts in unlikely spots. Wind erosion is most pronounced in arid areas that see little rainfall in areas of unbroken, smooth terrain. Storms composed of heavy rains and high winds pose a double threat to vulnerable soils, of which the effects are not always as apparent as in cultivated areas that experience change from farming practices.

Impact of Climate Change

• Conservationists pay particularly close attention to global climate changes evidenced by the marked increase of rainfall in some areas. Shifting rainfall patterns pose a threat to croplands, as planting seasons often coincide with more intense weather events, and the soil's existing water content may contribute to erosion. Any change in precipitation changes the risk level to which croplands are exposed, and could increase soil degradation, surface and groundwater pollution.

Causes and Effects

• Fertile soil production is a nonrenewable resource, as it takes hundreds of years, making erosion a crucial problem. According to the Maine Bureau of Land and Water Quality, erosion also damages aquatic habitats, impacts water quality, raises project costs, lowers values of shorefront properties, raises property taxes, and eliminates salmon and trout fisheries, which subsequently creates a loss of jobs and businesses. It's important to keep in mind that human intervention plays a key role, as deforestation, destruction of vegetation, overgrazing and over-farming accelerate the erosion process. Degrees of degradation range from light and moderate, which allow for some agricultural activity, to strong and extreme, which represent land that is no longer usable and cannot be restored.