Environmental Science MCQ Questions and answers | EVS MCQ

Water vapour, water vapour or aqueous vapour is the gaseous phase of water. It is one state of water within the hydrosphere. Water vapour can be produced from the evaporation or boiling of liquid water or from the sublimation of ice. Unlike other forms of water, water vapour is invisible. Under typical atmospheric conditions, water vapour is continuously generated by evaporation and removed by condensation. It is less dense than air and triggers convection currents that can lead to clouds.

It spilled 10.8 million US gallons (260,000 bbl) (or 37,000 metric tonnes) of crude oil over the next few days. It is considered to be one of the worst human-caused environmental disasters. The Valdez spill is the second largest in US waters, after the 2010 Deep water Horizon oil spill, in terms of volume released

In calm air the air temperature is -10o C, if the wind speed should increase to 30 knots (with no change in air temperature) the thermometer would indicate a temperature of -10^o C.

Infrared satellite technology works by sensing the temperature of infrared radiation being emitted into space from the earth and its atmosphere. Basically, all objects (including water, land, and clouds), radiate infrared light. However, our eyes are not "tuned" to see this kind of light, so we don't notice it. Weather satellites not only sense this infrared light, but they can also sense the temperature of the infrared emissions.
Visible satellite images can be thought of as photographs of the earth from space. Since they are like a photograph, they are dependent on visible light (brought by the sun). As a result, visible satellite pictures only work during daylight hours. This is the greatest drawback to using visible imagery. Also, since a visible satellite picture is basically a photograph, thicker clouds (which reflect the most sunlight) show up very bright, while thinner clouds (like cirrus) are hard to distinguish.

Relative humidity is a measure of the water vapour content of the air at a given temperature. The amount of moisture in the air is compared with the maximum amount that the air could contain at the same temperature and expressed as a percentage.

The greenhouse effect is the process by which radiation from a planet's atmosphere warms the planet's surface to a temperature above what it would be without this atmosphere.
Radiatively active gases (i.e., greenhouse gases) in a planet's atmosphere radiate energy in all directions. Part of this radiation is directed towards the surface, warming it. [3] The intensity of the downward radiation – that is, the strength of the greenhouse effect – will depend on the atmosphere's temperature and on the amount of greenhouse gases that the atmosphere contains.

A clear cloudless day-time sky is blue because molecules in the air scatter blue light from the sun more than they scatter red light. When we look towards the sun at sunset, we see red and orange colors because the blue light has been scattered out and away from the line of sight.

Heat energy from the earth's interior contribute to this heating.

The limits of tolerance and optimal range of distribution may vary in different seasons in some species of animals.If some environmental factors shifts beyond the limit of tolerance of organism: in such condition the organisms can come to the resting stage or migrate or the can be acclimatise them in new environmental conditions.

Salts enter the soil through irrigation; they originate either from geological layers, from groundwater or from man-made influences, such as fertilizers.
Crops vary in their reaction to soil salinity.