This document discusses evidence of climate change and drought, including the evolution of Earth's atmosphere over time. It provides data showing increases in global temperatures, rising sea levels, retreating glaciers, and other impacts. Specific impacts in India are also examined, such as increased drought frequency and effects. The document concludes by outlining typical drought impacts and strategies used in India to mitigate and prepare for drought conditions.

1. Evidences of Climate Change and Drought
BY
MEDIDA SUNIL
KUMAR

2. What is mean by climate?
What is mean by climate change?
What is mean by climatic variability?

3. Past Climate of Earth

4. Evolution of Earth’s Atmosphere
1. Earliest Atmosphere:
 Primarily H2, water vapor, CH4 and NH4 like Jupiter and Saturn.
2. Second Atmosphere:
Consisting largely of N2 plus CO2 and inert gases, was produced by volcanism
Early Sun put out 30% lower solar radiance associated one cold glacial phase about 2.4
billion years ago
Late Archaean eon O2 containing atmosphere began to develop, apparently produced by
photosynthesizing cyanobacteria
3. Third Atmosphere:
 Movement of plate tectonics and volcanism released CO2
Free oxygen did not exist in the atmosphere until about 2.4 billion years ago
The amount of oxygen in the atmosphere has fluctuated over the last 600 million years,
significantly higher than today's 21%.

5. Causes of Climate Change
Natural Causes
 Volcanoes
 Solar Output
 Earth's Orbit around the Sun
Anthropogenic Causes
 Fossil Fuels
 Industrial Revolution
 Change in Land use

8. Solar activity vs temperature

9. We Have Also Altered the Atmosphere
Greenhouse Gas
Pre-1750
Tropospheric
Concentration
Recent
Tropospheric
Concentration
Change in
Tropospheric
Concentration
Carbon dioxide (CO2) 280 ppm 400 ppm 40%
Methane (CH4) 700 ppb 1874 ppb 168%
Nitrous oxide (N2O) 270 ppb 324 ppb 20%
Chlorofluorocarbons (CFCs)
0 21-529 ppb NA
Ozone (O3) 25 ppb 34 ppb 36%

10. Evidence of Changing Climate
 Evaporation & rainfall are increasing
 Coastal glaciers are retreating
 Mountain glaciers are disappearing
 Permafrost is thawing
 Sea ice is shrinking
 Greenland is melting
 Sea level is rising
 Species are moving

11. Evaporation & Precipitation are increasing
NCDC, 2000
Effect is not uniform; most places getting wetter, some getting drier.

12. Coastal Glaciers Retreating
Muir Glacier, Alaska, 1941-2004
August 1941 August 2004
NSIDC/WDC for Glaciology, Boulder, compiler. 2002, updated 2006. Online glacier photograph
database. Boulder, CO: National Snow and Ice Data Center.

13. Glacier Retreating
1875 2004

15. Mountain glaciers are disappearing
Courtesy Lonnie Thompson

16. Permafrost is Thawing
Average annual ground temperature, Fairbanks, AK
°C
Permafrost melts when T ≥ 0°C ACIA 2004

17. Arctic Summer Ice is Shrinking
NASA photograph
1979 2003
 North Polar ice cap is sea ice -- it’s floating and so does not change sea level
when it melts.
 But the reduced reflectivity when the ice is replaced by water amplifies the
warming effect of greenhouse gases.

18. Summer surface melting on Greenland, 1979-2002
Greenland is melting
ACIA, 2004

19. Greenland melting (continued)
2005 broke the 2002 record

21. Sea Level
Data source: Coastal tide gauge records. Credit: CSIRO. 2012. Data source: Satellite sea level observations. Credit: CLS/Cnes/Legos. 2012

22. Sea-level from satellites: 4 cm rise in last 10 years

23. Rise in global ocean heat content 1955-2005
Some ups and downs, but clear overall increase
Levitus et al., 2005, GRL

25. Extreme weather events
Image Credit: http://www.grida.no/graphic.aspx?f=series/et-common/trends_L.gif

27. Global surface temperature 1855-2010

28. Observed surface temperature trend
Trends significant at the 5% level indicated with a ‘+’. Grey: insufficient data

29. Vulnerability of India to Climate Change

30. WHAT WILL HAPPEN IN THE CASE SEA LEVEL RISE ??

31. DROUGHT
 Drought is one of the most widespread complex and complicated
disasters.
 Extended period of deficient rainfall relative to normal's
 68% of the country’s geographical area is prone to drought in varying
degrees
 Chronically drought prone areas: – @ 33% (RF: <750 mm)
 Drought prone area: – @ 35% (750-1125 mm)
 Drought onset: Total rainfall deficiency is > 10 percent of normal's
 Severe drought: Total rainfall deficiency is > 25 percent of normal‘s

34. Chronology of drought and famine in India
Period No Region affected by famines/droughts
5th century BC 1 Kashmir , Ayodhya (eastern UP), Rajasthan, Gujarat,
Maharashtra & Punjab
1st century BC 1 Kashmir
9th century AD 1 Kashmir
10th century AD 2 Kashmir , Punjab, large parts of northern India
11th century AD 2 Delhi, Bihar , Bengal, Orissa, Rajasthan & Kashmir
13th century AD 4 Orissa, Bihar , Assam, Bengal, Rajasthan, Maharashtra & Gujarat
14th century AD 5 Delhi, Rajasthan, Maharashtra, Mysore, Karnataka & Gujarat
15th century AD 5 Rajasthan, Maharashtra, Orissa, Assam & most parts of India,
especially the areas along the rivers Ganga & Yamuna
16th century AD 6 Most of the then Bombay presidency, Punjab, Maharashtra, Delhi,
Rajasthan, Kutch & central India
17th century AD 6 Gujarat, Maharashtra, Rajasthan & Bengal
18th century AD 24 Bombay presidency , Gujarat, Maharashtra & Madras
19th century AD 38 Rajasthan, Gujarat, Orissa, Maharashtra, Andhra Pradesh,
Kashmir , Himachal Pradesh & Bihar
20th century AD 60 Rajasthan, Gujarat, Orissa, Andhra Pradesh, Kashmir, Himachal
Pradesh, Bihar , Maharashtra, Jammu &Kashmir
Source ‘Drought of Relief’, Down to Earth, May 2001

35. Typical Effects of drought
 Failure or loss of crops.
 Loss of dairy and fishery production.
 Reduced energy production.
 Increased unemployment
 Soil erosion.
 Acute shortage of drinking water.
 Health hazards and loss of life.
 Widespread poverty.
 Prices of all commodity shoot up.

36. Strategies adopted before drought at household level
• Crop diversification on/ crop variety diversification
• Livelihood diversification
• Staggering of seedling periods
• Early migration
• Keeping land fallow
• Limited re-sowing

37. Main mitigation strategies
 Early warning and response mechanisms
 Close monitoring of drought
 Augmentation of water supply and conservation
 Proper and scientific expansion of irrigation facilities
 Land use
 Inter-basin transfer of river waters
 Promoting Water-shed programmes