Date post: | 17-Jan-2017 |
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Environment |
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RECENTLY OBSERVED CLIMATIC CHANGES AND THEIR POSSIBLE CAUSES
Presented by: fs
OVERVIEW• Introduction• Recently observed changes•Main causes Internal forcing mechanism External forcing mechanism•Conclusion and suggestion
INTRODUCTION• The atmosphere is constantly changing so it is necessary to make a
distinction between genuine climate changes and day to day fluctuations in the weather.• The weather change from day to day, but we expect the climate to
remain relatively constant.
• If the climate doesn’t remain constant, we call it climate change.
RECENT OBSERVED CHANGES……
• Climate models predict 2-3.5°C increase in temperature and 250-500 mm increase in precipitation in the North Eastern region of India. • In 2013 alone, heat waves followed by cyclones and flood occurred in Orissa
displacing millions.• Landslide occurred near Kedarnath Temple with loud thunder followed by
gushing of huge amount of waters from Chorabari Tal or Gandhi Tal down Mandakini River.• Most glacier in the northern hemisphere shows a decrease in size resulting in
rise in level of pacific ocean.
• This winter’s weather has been weird across much of the Northern Hemisphere as it is too long than usual • Recently it is observed that European alps decrease one third of it’s
original size. This is a clear sign of an increase in temperature. • New ice cover record on the Great Lakes, sending the mercury as low as
minus 500 C in Minnesota, and bringing sharp chills to Texas.• Amazon rainforest actually slipped into reverse gear and started to emit
more carbon than it absorbed
CONTINUED…….
33% population of north-west India
suffers drought yearly(Bundelkhand (U.P.) )
Flood, landslides, storms, cyclones are faced yearly in different region leaving
thousands homeless.(kedarnath gulf flood, June
2013)
CHINA,2013, temperature falls 2.8 degree than
usual, results in ice all around .
Change in climate recorded by THE ANGRY
SUMMER
3.5% temperature increase in north-India
in june,2013
MAIN CAUSES•Internal forcing mechanisms
Orbital variationsMagnetic field strengthPlate tectonics•External forcing mechanisms
Solar outputVolcanismHuman influences
POSSIBLE CAUSES FOR CLIMATIC CHANGES
HUMN INFLUENCEVOLCANIC ERUPTIONORBITAL VARIATIONSOLAR OUTPUTPLATE TECTONICSOCEAN VARIBILITY
ORBITAL VARIATIONS, PLATE TECTONICS AND SOLAR OUTPUT • Slight variations in Earth's orbit lead to changes in the seasonal
distribution of sunlight reaching the Earth's surface and distributed across the globe.• Latest researches indicate that ionisation from cosmic rays
significantly enhances aerosol formation in the presence of sulphuric acid and water.• The motion of tectonic plates reconfigures global land and ocean
areas and affect both global and local patterns of climate and atmosphere-ocean circulation
.
VOLCANIC ERUPTION
•Volcanic eruption effect climate change since it send huge amount of particles into the air.• It cause climatic variation by partially blocking the transmission of solar radiation to the Earth's surface.
.
HUMAN INFLUENCE
Climate is changing and that these changes are in large part caused by human activities, and it is largely irreversible.CO2 and other harmful gases emission tends to green house effectDeforestationAerosols These causes results in global warming which is responsible for climate variability.
CO2 EMISSION• A number of harmful gases are responsible for change in
climatic condition.• CO2 plays a major role as it is more harmful without any
positive effect.• Levels of CO2 (and other harmful gases) have severely
increased to a very higher level
DEFORESTATION AND AEROSOLS IN ENVIRONMENT
•Deforestation by humans is causing all necessary functions of trees to be lessened, and hence damaging the atmosphere dramatically .•Aerosols are found in urban Ecosystems in various forms-
Dust,Cigarette smoke,Mist from aerosol spray cans,Soot or fumes in car exhaust.
The presence of aerosols in earth's atmosphere influence Earth's climate, as well as human health
CONCLUSION AND SUGGESTIONS•As per the results none of the causes effect more than 2-3% of what is caused by human activities.•The rains are erratic, winters have become warmer, and the summers longer , the average temperature in many places stayed above normal
And above all, climate is still changing……… To reduce the human influence on the climatic changes:
•Forestation should be adopt.•Combustion of fossil fuel must be reduced.•CFC products and other harmful chemicals should be avoided.•Government should make some rules for the mountain visiting pilgrims.