GREENHOUSE EFFECT

Greenhouse Effect

Table of Contents

Introduction1

What is greenhouse Effect?1

Discussion2

Gases "Greenhouse Effect"2

Effects of human activities4

Greenhouse Gas5

The Greenhouse Effect and Micro- and Nano-Particles in the Atmosphere11

Climate Change as an Issue of Sustainability and Equity11

Conclusion12

References14

Greenhouse Effect

Introduction

Common usage of this term is a generalization of the phenomenon known empirically that allows greenhouses to maintain the cultures at a higher temperature."The greenhouse effect" is due to the presence of greenhouse gases (GHG) content in the atmosphere. A portion of solar radiation through the atmosphere and reaches the ground, which in turn emits thermal radiation which it is absorbed by greenhouse gases, warming the atmosphere, which in turn warms the soil (in the case of the Earth's crust, the biosphere and the hydrosphere)

What is greenhouse Effect?

The greenhouse effect is a natural process that, for a given absorption of electromagnetic energy, from the Sun (in the case of solar system bodies) and other stars (in the general case), gives the body which receives this energy a surface temperature well above a situation "without the greenhouse effect." It is found on various celestial objects in the solar system, including Venus.

Discussion

When the radiation sun reaches the earth's atmosphere, a portion (approximately 30%) is directly reflected, that is to say, back into space, through the air, the clouds white and bright surface of the Earth, especially the white areas and ice as the Arctic and the Antarctic which is not shown in the diagram. The incident rays that are not reflected back to space is absorbed by the atmosphere (20.7%) and surface (51%).

The latter part of the radiation absorbed by the surface it brings heat, i.e. the energy, it restores to turn day and night, toward the atmosphere as infrared rays (in the range 8-13 microns mainly). This is the "radiance of the black body.” This radiation is then absorbed in part by greenhouse gases, warming the atmosphere. Then a third time, this heat is re-emitted in all directions, some escapes into space, but another part returns to Earth and is an additional contribution of heat to the surface (Rebecca, 1993).

Gases "Greenhouse Effect"

The greenhouse gases are gaseous components of the atmosphere that contribute to the greenhouse effect. These gases have the common characteristic of absorbing some of the infrared emitted by the Earth's surface.

The main greenhouse gases are water vapor, the carbon dioxide (CO 2), methane (CH 4), the nitrous oxide (or nitrous oxide of the formula N 2 O) and the Ozone (O 3). Greenhouse gas emissions include industrial heavy halocarbons (chlorinated fluorocarbons including CFCs, and the sulfur hexafluoride (SF 6).

Estimated contributions to the greenhouse effect of the main gas, according to the IPCC :

Steam: 60%

Carbon dioxide : 26%

Ozone : 8%

Methane and nitrous oxide : 6%

Taking into account the greenhouse effect of clouds, all water vapor + cloud is at least 90% of the greenhouse effect.

Effects of human activities

Most greenhouse gas (GHG) emissions are from natural. But some of them are solely due to human activity or see their concentration in the atmosphere increase as a result of this ...