Climate includes patterns of temperature, precipitation, humidity, wind and seasons.
"Climate change" affects more than just a change in the weather, it refers to seasonal changes over a long period of time. These climate patterns play a fundamental role in shaping natural ecosystems, and the human economies and cultures that depend on them.
Because so many systems are tied to climate, a change in climate can affect many related aspects of where and how people, plants and animals live, such as food production, availability and use of water, and health risks.And now when people talk about climate change they always talk about green house effect.
What is greenhouse effect?There are two meanings of the term “greenhouse effect”. There is a “natural” greenhouse effect that keeps the Earth’s climate warm and habitable. There is also the “man-made” greenhouse effect, which is the enhancement of Earth’s natural greenhouse effect by the addition of greenhouse gases from the burning of fossil fuels. About 80-90% of the Earth’s natural greenhouse effect is due to water vapour, a strong greenhouse gas. The remainder is due to carbon dioxide, methane, and a few other minor gases.
In order to understand how the greenhouse effect operates, we need to first understand “infrared radiation”. Greenhouse gases trap some of the infrared radiation that escapes from the Earth, making the Earth warmer that it would otherwise be. You can think of greenhouse gases as sort of a “blanket” for infrared radiation, it keeps the lower layers of the atmosphere warmer, and the upper layers colder, than if the greenhouse gases were not there.
Natural greenhouse effectOur atmosphere is relatively transparent to the wavelengths of sunlight, but not to the thermal radiation that is emitted from the Earth’s surface. This radiation
does pass through the primary gases in the atmosphere – nitrogen, oxygen and argon – but carbon dioxide, water vapour and some other so-called greenhouse gases absorb a large proportion of the thermal radiation.This means that when there is equilibrium between the incident radiation from the sun and the emitted radiation from the Earth
quite a lot of heat is stored in the atmosphere. One consequence of this is that the temperature on the Earth’s surface is higher than it would have been if the atmosphere had not contained greenhouse gases, in fact 33°C warmer.This is the natural greenhouse effect.
man made green house effectEmissions of greenhouse gases mean that the natural greenhouse effect is reinforced. A larger quantity of heat is circulated (captured and re-radiated) in the lower regions of the atmosphere when the incident radiation and emitted radiation are in equilibrium, which means that the temperature on the Earth’s surface rises.
The harmful effects of presence of greenhouse gasses in atmosphere are global warming, climate change, ozone depletion, sea level rise, adverse effects on biodiversity etc.One way or another these adverse impacts are all directly or indirectly related to the presence of greenhouse gases in the atmosphere. A number of human activities, processes and consumptions produce waste gasses or greenhouse gasses that are harmful to the environment. They include:
(a) Fuel combustion
(b) Energy industries
(c) Manufacturing industries and construction
(d) Vehicle Transport and automobiles
(e) Fugitive emissions from fuels
(f) Burning of solid fuels
(g) Use of oil and natural gas
(h) Mineral products
(i) Chemical industry
(j) Metal production
(k) Production of halocarbons and sulfur hexafluoride
(l) Consumption of halocarbons and sulfur hexafluoride
(m) Solvent and other product use
(n) Enteric fermentation
(o) Manure management
(p) Rice cultivation
(q) Agricultural soils
(r) Prescribed burning of savannas
(s) Field burning of agricultural residues
(t) Solid waste disposal on land
(u) Wastewater handling
(v) Waste incineration
What are the Effects?The Earth has warmed an average of 1.1ºF (0.6 ºC) since
the beginning of the Industrial Revolution in 1880.
Although this may seem like a small increase in temperature, it
is a dramatic change relative to the last several hundred years
or more. It is widely thought that the increase in temperature is
largely caused by the human-induced increase of greenhouse
gas concentrations in the atmosphere.
· Land and ocean temperatures rise
· North and South Poles (Arctic and Antarctic) melt
· Glaciers melt
· Ocean currents change
· Weather patterns change
· Sea levels rise (due to oceans warming the water ‘swells’ and there’s more water as polar regions melt )
Composition of the atmosphere78% nitrogen
20.6% oxygen
< 1% argon
0.4% water vapor
0.036% carbon dioxide
traces gases:
Ne, He, Kr, H, O3
Methane, Nitrous Oxide
green house gasesCarbon Dioxide (CO2)
Source: Fossil fuel burning, deforestation
Anthropogenic increase: 30%
Average atmospheric residence time: 500 years
Methane (CH4)
Source: Rice cultivation, cattle & sheep ranching, decay from landfills, mining
Anthropogenic increase: 145%
Average atmospheric residence time: 7-10 years
Nitrous oxide (N2O)
Source: Industry and agriculture (fertilizers)
Anthropogenic increase: 15%
Average atmospheric residence time: 140-190 years
Greenhouse gases absorb infrared radiation and prevent it from escaping to space.
Carbon dioxide, methane, and nitrous oxide are very good at capturing energy at wavelengths that other compounds miss.
An increase in the concentration of greenhouse gases leads to an increase in the the
magnitude of the greenhouse effect.This is Called enhanced greenhouse effect. This is
what we should be afraid of.Because this causes global warming!!!!!