working of environment

8/4/2019 Working of Environment

1/30

ENVIRONMENTAL THREATSA Climatology project

By

Alma Kerketta

101110115

Section - B


2/30

GLOBALWARMING

The term "global warming" refers to the increasein the average temperature of global surface air andoceans since about 1950, and to continuingincreases in those temperatures.

Another term for "global warming" is "climatechange."

"The global surface temperature is an estimate ofthe global mean surface air temperature. However,for changes over time, only anomalies... are used,most commonly based on the area-weighted globalaverage of the sea surface temperature anomalyand land surface air temperature anomaly."


3/30

CAUSES

Too many greenhouse gases in the earth'satmosphere will increase the greenhouse effect

The most dangerous aspects of the continuingdramatic climatic change is the effects of feedbackloops (amplified change).

As the earth warms, the levels of ice and snowdecrease.

This decrease leads to higher temperatures onthe surface, leading to more warming.


4/30

HIGHLIGHTSOF THECAUSES

1. Carbon Dioxide From power Plants

Largest contributors power plants

Approximately 40% of all carbon dioxide emissions

comes form power plants2. Pollution Emitted from Cars

Cars emit millions of tons of pollutants into the air.

This causes some of the smog and ozone problems


5/30

HIGHLIGHTSOFCAUSES

3. Pollution from Trucks

Trucks, although less in volume, make up for alarge portion of the earth's pollution

Diesel, the standard for trucks is known to be lessclean than gasoline.

4. Pollution from Airplanes

10% of the green house gas emissions come from

airplanes.


6/30

HIGHLIGHTSOFCAUSES

5. Pollution from Buildings

The houses we live in may be a larger contributor toit

Houses are mainly built to burn oil, or run on coal.In most houses, coal is used for electricity becauseit is the cheapest and most abundant resource.


7/30

HIGHLIGHTSOFCAUSES

6. Methane Stored in Water and Ice

With the increase in temperature, a fear of methanebeing released into the air arises.

Methane is approximately 60 times stronger thancarbon dioxide as a green house gas.

In the past, when the earth's temperature rose to acertain level, such as 8 degrees above normal, theearth's temperature then increased an additional 14degrees.


8/30

SOLUTIONS

Products that help to reduce the green houseemissions have emerged. Filters that improve thequality of the air released into the atmosphere havebeen created to solve this problem.

Government regulations have been placed to forceowners of large industrial buildings to improve thequality of the air produced by their buildings.

Hydrogen power has also become a way of

reducing carbon.


9/30

SOLUTIONS

One thing that can be done is a switch to moreenvironmentally friendly vehicles such as hybrid orelectric cars.

Some countries are even using cars that run onhydrogen.

Ethanol to replace gasoline in cars seems to be apromising change.

Although airplanes do pollute the sky, theyaccidentally reflect some sunlight.


10/30

SOLUTIONS

Architects will have to start using materials that canreduce the consumption of fuels by making thembetter ventilated or better at holding in heat.

Government regulators must pass laws forcingcontractors to follow stricter guidelines whenbuilding homes to reduce energy consumption.


11/30

EFFECTS

Prediction says that even if we stopped emittingheat-trapping gases immediately, the climate wouldnot stabilize for many decades because the gaseswe have already released into the atmosphere will

stay there for years or even centuries. The increased volumes of carbon dioxide and other

greenhouse gases (GHGs) released by the burningof fossil fuels, land clearing and agriculture, andother human activities, are the primary sources of

the human-induced component of warming. Anincrease in global temperatures can in turn causeother changes, including a rising.


12/30

EFFECTS

1. Recognition of global warming

Melting of glaciers Most of the mountain glaciers onour planet that have been monitored for the past150 years are reportedly shrinking.

The glaciers most affected by global warming thoselocated in the lower latitudes and many of them aredisappearing.

If glaciers continue to shrink, it could affect watersupply in areas that depend heavily upon mountainwatersheds.


13/30

EFFECTS

Ocean warming Sea level increase is attributed towarmer temperatures, which in turn result to themelting of ice glaciers.

Over the last 100 years, sea level has increasedfrom 10 cm to 25 cm. Projections over the nexthundred years indicate that sea level will risehigher, from about 15 cm to 90 cm.


14/30

CLIMATECHANGEDUETO

GLOBALWARMING

The earth's climate has always been changing,although not at an abrupt rate.

There had been periods of warming and cooling inthe earth's 4.65 billion-year history.

Global warming will raise the temperatures in someregions of the Northern Hemisphere, causing themelting of mountain glaciers.

This means that areas that are currentlyexperiencing light snow may no longer experiencesnowfall anymore.


15/30

CLIMATECHANGEDUETO

GLOBALWARMING

Snowlines found in mountains in temperate regionsmay also be higher and packs of snow will meltearlier than before.

Spring may be experienced earlier andtemperatures during night time and in winter willrise.

The world will experience a more humidatmosphere since sea water will have a higher rate

of evaporation.

With greater humidity, rainfall is expected toincrease on average.


16/30

CLIMATECHANGEDUETO

GLOBALWARMING

Storms will also occur with more frequency andintensity.

Ironically, water in the soil will evaporate faster,causing dryness between rains. Regions that arealready considered dry will experience moredryness.

With warmer weather, some hurricanes will be moresevere and winds are expected to blow stronger. It

is also possible that wind patterns may shift.


17/30

CLIMATECHANGEDUETO

GLOBALWARMING

Extremely cold periods may be experienced aswell.

With changes in climate brought about by globalwarming, health concerns and risks may alsoincrease.

Heat stress and diseases may become common inplaces that did not have any problems with thembefore.


18/30

GREENHOUSEEFFECT

Carbon dioxide, methane, and nitrous oxide aresome of the main compounds that we are releasingmore and more, causing something known as theGreenhouse Effect'.

While a little greenhouse gas helps to keep ourplanet warm, the more and more that we release,the hotter the planet is going to get.


19/30

GREEN HOUSE EFFECT


20/30

GREENHOUSEEFFECT

Although greenhouse gases make up only about 1percent of the Earth's atmosphere, they regulateour climate by trapping heat and holding it in a kindof warm-air blanket that surrounds the planet.

This phenomenon is what scientists call the"greenhouse effect." Without it, scientists estimatethat the average temperature on Earth would becolder by approximately 30 degrees Celsius (54

degrees Fahrenheit), far too cold to sustain ourcurrent ecosystem.


21/30

GREENHOUSEEFFECT

How Do Humans Contribute to the Greenhouse

Effect?While the greenhouse effect is an essentialenvironmental prerequisite for life on Earth, there

really can be too much of a good thing.

The problems begin when human activities distortand accelerate the natural process by creatingmore greenhouse gases in the atmosphere than

are necessary to warm the planet to an idealtemperature.


22/30

CAUSESOFGREENHOUSEEFFECT

Burning natural gas, coal and oil -includinggasoline for automobile engines-raises the level ofcarbon dioxide in the atmosphere.

Some farming practices and land-use changesincrease the levels of methane and nitrous oxide.

Many factories produce long-lasting industrialgases that do not occur naturally, yet contributesignificantly to the enhanced greenhouse effect and

"global warming" that is currently under way.


23/30


Deforestation also contributes to global warming.Trees use carbon dioxide and give off oxygen in itsplace, which helps to create the optimal balance ofgases in the atmosphere.

As more forests are logged for timber or cut downto make way for farming, however, there are fewertrees to perform this critical function.


24/30


Population growth is another factor in globalwarming, because as more people use fossil fuelsfor heat, transportation and manufacturing the levelof greenhouse gases continues to increase.

As more farming occurs to feed millions of newpeople, more greenhouse gases enter theatmosphere.


25/30

OCCURRENCEOF

GREENHOUSEEFFECT


26/30

WHATISTHEOZONELAYER?

The ozone layer is a deep layer in the stratosphere,encircling the Earth, that has large amounts ofozone in it. The layer shields the entire Earth frommuch of the harmful ultraviolet radiation that comes

from the sun.

The ozone layer became more widely appreciatedby the public when it was realized that certainchemicals mankind manufactures, called

chloroflurocarbons, find their way up into thestratosphere where, through a complex series ofchemical reactions, they destroy some of theozone.
http://www.weatherquestions.com/What_is_the_stratosphere.htmhttp://www.weatherquestions.com/What_is_the_stratosphere.htm


27/30

OZONELAYERDEPLETION

Causes of Ozone Depletion The cause of ozone depletion is the increase in the level

of free radicals such as hydroxyl radicals, nitric oxideradicals and atomic chlorine and bromine.

The most important compound, which accounts for

almost 80% of the total depletion of ozone in thestratosphere are chlorofluorocarbons (CFC).

These compounds are very stable in the loweratmosphere of the Earth, but in the stratosphere, theybreak down to release a free chlorine atom due toultraviolet radiation.


28/30

CAUSESOF

OZONELAYERDEPLETION

A free chlorine atom reacts with an ozone molecule(O3) and forms chlorine monoxide (ClO) and amolecule of oxygen.

Now chlorine monoxide reacts with an ozone

molecule to form a chlorine atom and twomolecules of oxygen.

The free chlorine molecule again reacts with ozoneto form chlorine monoxide. The process continues

and the result is the reduction or depletion of ozonein the stratosphere.


29/30

EFFECTSOF OZONEDEPLETION Harmful effects of ultraviolet rays.

The ozone layer is responsible for absorbing theultraviolet rays and thereby preventing them frompassing through the atmosphere of Earth.

Ultraviolet rays of the Sun are associated with a numberof health related and environmental issues.

The most important of these is the association betweenultraviolet rays and an increased risk of developingseveral types of skin cancers including malignant

melanoma, basal and squamous cell carcinoma. Even the incidents of cortical cataracts can also

increase significantly with the increased exposure toultraviolet rays.


30/30

THANK YOU

working of environment

Documents