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
#question what is the diff, urogenital system of the invertebrae animal?

Japanese encephalitis  Japanese encephalitis is an uncommon but potentially fatal mosquito-borne viral disease that occurs in rural Asia, especially near pig farms and rice pad

Determine the main four events of bone remodeling Quiescence refers to the resting state of the bone surface. This includes all of the bone surfaces. Activation is the recr

Explain the Behavioural change communication? One of the reasons for the widespread prevalence of PEM in our country is ignorance due to illiteracy, particularly among the fema

Pericardial Effusion:  Indications for Surgery: Pericardial effusion may be the result of peiicarditis due to infection, autoimmune disease or neoplasm. Non-inflammatoly diseases

State the terms - Blastocoel and Blastopore? During the development of embryo, single cells divide and form a hollow ball of cells one cell layer thick. Cavity inside this holl

Explain the molecular difference between fats and oils. How do the differences affect their physical properties?

Venous Thromboembolism Prolonged immobilization (>8 hours) increases the risk of lower extremity deep vein thrombosis (DVT), particularly in travelers with risk factors for th

Salmonellosis is the most reported zoonotic disease in European countries. Salmonellosis (Salmonella gastroenteritis) results from the ingestion of foods that contain significant n

Question 1 What is chromatography? List various methods of chromatography. Add a note on applications of chromatography in diagnosis Question 2 Discuss the applications of co