The effect of snow on land and climate

Arab Weather - Most people love the winter season with its rain and snow because it is linked to the increase in the good of the earth, and the white visitor always brings happiness to the souls, so does snow bring happiness to our planet as well?

Seasonal snow is an important part of the earth's climate system, as the snow cover helps regulate the temperature of the earth’s surface, and the water resulting from the melting of this snow helps fill rivers and reservoirs in many regions of the world. When we talk about snow cover we mean the area of ​​land that covered by snow accumulated, snowy Valgueta the largest component of the ice cover in terms of area, covering an average of about 46 million km ² of the surface of the Earth each year, and is located about 98% of the ice cover of the land in the northern Hemisphere.

(An image showing the average area of ​​snow cover in the northern hemisphere, which reaches its maximum in January (left) and a minimum in August (right))

The effect of snow cover on the ground

Snow cover contributes to maintaining the Earth's temperature balance, through some of its unique properties such as reflection and insulation, but how does this happen?

Transflective (Reflectance)

White snow has a high reflection property of sunlight, as snow cover reflects about 80-90% of the sun’s energy into the atmosphere, while trees, plants and soil only reflect 10-30% of sunlight, and this effect appears more during the spring season (from April To May in the Northern Hemisphere), when the days get longer and the amount of sunlight increases over snow-covered areas, the high reflectivity of the snow helps cool the planet, helping to maintain the Earth's temperature balance.

Insulation (Insulation)

In addition to helping cool the ground, the snow cover also helps keep the earth warm, as the snow cover acts like an insulating blanket and maintains the heat of the earth underneath it. A layer of snow of 30 cm thickness is sufficient to protect the soil and living organisms from the drop in the temperature of the air above the surface The snow.

The surface of cold and wet snow also affects the amount of heat and moisture exchanged between the earth and the atmosphere, so snow helps to retain heat and prevent moisture from evaporating into the atmosphere, so that the snow cover on other materials, such as permafrost, river ice or sea ice, prevents the spread of Ice under it.

And there is another benefit of the snow cover on the soil, when the soil freezes it traps gases such as carbon and methane, which prevents them from being released into the air and the atmosphere, as carbon and methane are considered greenhouse gases that cause global warming, and the frozen soil prevents the movement of water inside the soil and on the soil surface, Since the soil surface is frozen, it absorbs less liquid water which may increase runoff.

Terrain and snow

There are several factors that affect the amount of snow accumulated in a particular area, in addition to the latitude at which the area is located and the time of year, differences in elevation, vegetation cover, the proximity of the region to the coast, prevailing wind and weather patterns contribute to the creation of different snow climates, except Differences in terrain and winds often cause changes in snow climates on small scales, as winds can scrape snow off a slope and deposit snow on the other side, causing the snow depth to vary ten times over the same mountain.

Climate effects on snow

While snow cover affects the climate, climate changes also affect snow cover, as climate changes and high temperature can lead to less snowfall, cause early melting of snow, and thus a decrease in snow cover, and this has a great impact on the amount of water resulting from melting snow that supplies Rivers, lakes and reservoirs