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.