GLOBAL CLIMATE CHANGE-FACTS

By: Dr. Vinay Kumar Pandey

Ph.D., M.Sc. (Geology), M. Sc. (Disaster Mitigation)

E-mail: vinay78pandey@gmail.com

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CLIMATE CHANGE

Climate change is a

significant and lasting

change in the statistic

distribution of weather

patterns over periods

ranging from decades to

millions of years.

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CAUSES OF CHANGE IN GLOBAL CLIMATE

• Change in Earth Orbit

• Variable Solar

Radiation/Output

• ALBEDO (Reflectivity)

Effects

• Greenhouse effects

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• The concept of Milankovitch Cycles was developed by the Serbian

mathematician Milutin Milankovitch (1930). They take account of

three variations in the orbit of the earth around the sun.

• Earth orbit changes from being nearly circular to slightly elliptical.

This cycle affected by other planets in the solar system.

• The angle of tilt of the earth axis changes from 22.1⁰ to 24.5⁰.

• The direction of the tilt of the axis changes (precession) on a cycle of

26,000 years.

These changes define the sequence of ice ages and warm periods.

1. CHANGE IN EARTH ORBIT- MILANKOVITCH CYCLES

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These changes influence the length of the seasons and the amount of solar radiation received by the earth and define the sequence of ice ages & warm ages.

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It appears that our Sun does not transmit a constant

intensity of radiation: observations indicate a variability of

0.1-0.2%. If solar output decreases for a period of time, it

causes cooling on Earth.

Although sunspot activity is cyclical (22 years), we do not

currently have an accurate concept of how solar output

has changed (and will change) on longer time scales.

2. VARIABLE SOLAR RADIATION

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3. ALBEDO EFFECTS

It is defined as the ratio of reflected radiation from the surface to incident radiation upon it.

It may expressed as a percentage, and is measured on a scale from zero for no reflecting power of a perfectly black surface, to 1 for perfect reflection of a white surface.

Ocean water have low albedo whereas land masses have moderate albedo. The highest albedo is snow and ice (very light in color).

Hence, periods when polar ice becomes very extended will promote further cooling.

Dust in the atmosphere has the same effect: it forms a high albedo veil around the Earth, so that much solar radiation is reflected before it reaches the surface. The dust may come from dry climate periods, volcanic eruptions or other means.

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ALBEDO EFFECT

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REFLECTED PERCENTAGE

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4. GREENHOUSE GASSES

The greenhouse effect is a process by which thermal radiation from a planetary surface is absorbed by atmospheric greenhouse gases, and is re-radiated in all directions.

If there is no greenhouse gases, the earth would be radiate energy into space and average global temperature would be (-) 15⁰C.

Greenhouse gases reduce the net radiation loss and stabilized the average global temperature.

Without this effect, the Earth would be cold and inhospitable.

Main greenhouse gases & their percentage on earth are:

Water vapor, 36-70%

Carbon dioxide, 9-26%

Methane, 4-9%

Ozone, 3-7%

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Huge volume of Carbon dioxide are injected into the ocean and atmosphere

during plate tectonic activities as earthquake and volcanoes.

The annual transported of carbon to & from the land surface & the atmosphere

and the ocean & the atmosphere is estimated 120 GtC (Gigatonnes of Carbon)

& 90 GtC respectively, and total natural emission is 210 GtC.

The annual emission of Carbon dioxide to the atmosphere resulting from

human activity is, by comparison, about 7 GtC (about 3% of total natural

annual emissions from the biosphere and the ocean).

Change in the natural transport of carbon, as well as human activity, have led

to recent increases in atmosphere concentration of carbon dioxide.

PLATE TECTONICS AND GREENHOUSE EFFECTS

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Natural CO2 emission sources 05/03/2013 15

There is no single instrument measuring climate change. Instead there are thousands of measuring devices spread across the globe, on land, under the sea and in the air.

Physical evidence for and examples of climatic change:

EVIDENCES OF PAST GLOBAL CLIMATE CHANGES

1) Temperature measurements and proxies 7) Precipitation

2) Historical and archaeological evidence 8) Dendroclimatology

3) Glaciers 9) Ice cores

4) Arctic sea ice loss 10) Animals

5) Vegetation 11) Sea level change

6) Pollen analysis

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VARIATION OF TEMP. AND CARBON DIOXIDE IN EARTH LIFE CYCLE

This graph indicates that there is no direct relationship between CO2 percentage in the atmosphere and global temperature. CO2 was much higher in past.

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Co2 concentration Temperature graph

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Graph indicates recent year relation between global climate change, CO2 percentage and Sunspots.

No direct relation of CO2 in global climate change. 05/03/2013 19

. Graph indicates that temperature varies as Solar irradiance change. Presently Solar Irradiance is decreasing so global temp should be low.

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CLIMATE VARIAION IN THE LAST MILLION YEARS

Warm age & Ice age is natural cycle. Previously earth was comparatively warm and cold as per current climate.

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Fact 1. Climate change is a constant. The Vostok Ice Cores show five brief interglacial periods from 415,000 years ago to the present. The Greenland Ice Cores reveal a Minoan Warm Period 1450-1300 BC, a Roman Warm Period 250-0 BC, the Mediaeval Warm Period 800-1100AD, the Little Ice Age and the late 20th Century Warm Period 1900-2010 AD.

Fact 2. Carbon dioxide is necessary for all life on earth and increasing atmospheric concentrations are beneficial to plant growth, particularly in arid conditions.

Fact 3. The twentieth century was almost as warm as the centuries of the Mediaeval Warm Period (1450-1300 BC), an era of great achievement in European civilisation. The recent warm period, 1976-2000, appears to have come to an end and astro-physicists who study sunspot behavior predict that the next 25-50 years could be a cool period similar to the Dalton Minimum of the 1790s-1820s.

NINE FACTS ABOUT CLIMATE CHANGE -RAY EVANS (Nov 2006)

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Fact 4. The evidence linking anthropogenic (man-made) carbon dioxide emissions and current warming is limited to a correlation which holds only for the period 1976 to 2000. Attempts to construct an holistic theory in which atmospheric carbon dioxide controls the radiation balance of the earth, and thus determines average global temperatures, have failed.

Fact 5. The anthropogenists claim that the overwhelming majority of scientists are agreed on the anthropogenic carbon dioxide theory of climate control; that the science is settled and the debate is over; and that scientific sceptics are in the pay of the fossil fuel industries and their arguments are thus fatally compromised. These claims are an expression of hope, not of reality.

Fact 6. Anthropogenists blame, anthropogenic emissions of CO2 for high temperatures, droughts, melting polar ice caps, rising sea levels and retreating glaciers, and a decline in the polar bear population.

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Fact 7. They also blame anthropogenic CO2 for blizzards, unseasonable snow, freezing weather generally and for hurricanes, cyclones and other extreme weather events. There is no evidence at all to justify these assertions. Increasing atmospheric concentrations of carbon dioxide will have negligible impact on the earth’s radiation balance and will promote plant growth everywhere.

Fact 8. 'Tropical' diseases such as malaria and dengue fever are not related to temperature but to poverty, lack of sanitation and the absence of mosquito control practices.

Fact 9. The decarbonisation of the world's economy would, if attempted, cause huge economic dislocation. Any democratic government which seriously sought to fulfill decarbonisation commitments would lose office. Shutting down coal-fired power stations and replacing them with renewable energy sources such as windmills or solar panels will cause unemployment and economic deprivation.

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The sun turns through 180 degrees every 11 years and our earth

orbit comes close to the same parts of the sun that it came

close to 11 years earlier.

The graph below shows the solar-cycles in global temperatures reasonably clearly. The vertical grid lines are 11-year solar cycle intervals and the solid thin line is the annual mean global surface temperatures, as published by the Australian Bureau of Meteorology.

The mean temperature for each 11-year solar cycle interval is shown by the dashed horizontal lines and that value is written in each interval. For example, the last solar cycle from 1999 to 2010 averaged 14.39 degrees C – the hottest 11-year solar cycle since the end of the

mini ice age in 1850. (Source: Ian Levy, Jan 2012)

SOLAR CYCLE AND GLOBAL TEMPARATURE

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SOLAR CYCLE AND GLOBAL TEMPARATURE

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On the basis of above graph Solar Cycle and Global Temperature, following results comes out:

There appears to be a strong, solar-related cyclical pattern in global temperatures. Why can’t the overall warming trend also be predominantly solar-induced and not human-induced?

Human-induced CO2 increased strongly from 1878 to 1911 but global temperatures fell quite strongly for 33 years – this 33 years of non-correlation between human-induced CO2 build-up and falling global temperatures for 33 years cannot be ignored as a minor aberration.

Human-induced CO2 increased strongly from 1944 to 1977 but global temperatures did not rise – they actually fell. Again, this 33-year period of non-correlation with CO2 cannot be ignored.

If CO2 is the dominant control on global temperatures, why don’t temperatures increase steadily in proportion to CO2 levels rather than in a cyclical manner that seems to be more related to the sun’s seasonal thermal cycles?

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Prediction of future global climate ( Decrease in temp) change, on the basis of Milankovitch Cycles.

Present Time Future Past Age 05/03/2013 29

Observed surface warming graph are differ from predicted temperature graph. Surface temp has been falling since year 2010.

Observed Temp.

Predicted Temp

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Global average temp increased + 1.44°C from year 1983 to 1997. AND CO2 concentration increased by 343 to 364 ppm.

Global average temp decreased (-) 0.08°C from year 1998 to 2012. AND CO2 concentration increased by 364 to 394 ppm.

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Climate change is a constant feature of Earth.

Human-induced CO2 will increase strongly for at least the next 33years as China and India industrialise. If global temperatures do not rise significantly during this next 33-year period, will we conclude that this was a result of political action against “climate change” or will we conclude that it is probably part of a long-term solar cycle?

Anthropogenic (man made) activities are not playing major role in present climate change.

Intergovernmental Panel of Climate Change (IPCC) data has been confirmed that despite of massive increase in anthropogenic activities CO2, global temperature goes down & it is differ from prediction.

There is no direct relation in concentration of Carbon dioxide in atmosphere and global temperature.

CONCLUSION

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Nine Facts about Climate Change- Ray Evans, Nov 2006,

Published by Lavoisier Group.

A Watershed Year for Global Temperature Trends?

Update- Ian Levy, Jan 2012.

Various Internet sites.

References

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