Periodic variations in light-diurnal and seasonal, Biology

Periodic Variations in Light-Diurnal and Seasonal

We know that rotation of the earth on its axis accounts for day-to-night variations in the amount of radiations falling at a given place and seasonal variations occur due to the orbiting of the earth around the sun. Since the earth's equatorial plane is inclined to its orbit at an angle of 23o.27'. the rays of the sun do not fall vertically on all parts of the earth. From March 22nd to Sept. 22nd (AutumnaTequinox), the northpole is inclined towards the sun. So the most intense solar beam is focused on the northern hemisphere. We in the northern hemisphere, have summer season and on the northpole the sun shines for 24 hours of the day. While on South pole it is dark for six months and the southern hemisphere has winter season. The opposite situation exists on the poles from September 24 to March 20 (spring equinox) when the northern hemisphere has winter season and southern hemisphere has
summer season (Figure shown below).

1739_periodic varaitions.jpg

There is also horizontal variation in the distribution of radiation on the earth. Because the earth is nearly spherical in shape, parallel beam of incoming sunlight does not fall vertically on all parts of the earth. It strikes lower latitudes more directly than higher latitudes. Therefore, at higher latitudes the incident radiation falls obliquely on the surface, travels more through the atmosphere, and spreads over a greater area and thus is less intense than the vertical beam falling on or near the equator.

 

Posted Date: 12/10/2012 6:10:49 AM | Location : United States







Related Discussions:- Periodic variations in light-diurnal and seasonal, Assignment Help, Ask Question on Periodic variations in light-diurnal and seasonal, Get Answer, Expert's Help, Periodic variations in light-diurnal and seasonal Discussions

Write discussion on Periodic variations in light-diurnal and seasonal
Your posts are moderated
Related Questions
The active transport of molecules requires an input of metabolic energy and this can  be  derived  either  from  direct  coupling  to  the  hydrolysis  of  ATP  or  by coupling to

Define Mutual supplementation of Protein with legume and milk? Improvement of cereal diets with legume and milk proteins: The proteins of poor diets based on different cereals

A (w+/ w+) red-eyed Drosophila female is crossed with a white-eyed male. Assuming the trait for eye colour is sex-linked, what are the possible phenotypes of the progeny?

describe how ulcers can lead to distention and irritation followed by vomiting?

ROL E OF NUCLEIC ACIDS - These are DNA / RNA. Unit is nucleotides. Present in viruses and all cells. DNA is concerned as genetic material. RNA as genetic material

List out the endothermic and exothermic reactions taking place in our body

Nitrogen is very important constituents of all organisms life  because it forms the structural parth of proteins, nucleic acids and chlorophyll molecules.               Earth 's

detail study of coelenterata

when does it started?

How many alleles of genes that condition X-linked traits do female and male individuals respectively present? For every correspondent gene to an X- linked trait women present a