Thursday, November 8, 2012

Global Warming: Climate Change And Green Policy

Global warming   
Since the early 20th century, Earth's mean surface temperature has increased by about 0.8 °C (1.4 °F), with about two-thirds of the increase occurring since 1980. Warming of the climate system is unequivocal, and scientists are more than 90% certain that it is primarily caused by increasing concentrations of greenhouse gases produced by human activities such as the burning of fossil fuels and deforestation.These findings are recognized by the national science academies of all major industrialized nations.
Global mean land-ocean temperature change from 1880–2011, relative to the 1951–1980 mean. The black line is the annual mean and the red line is the 5-year running mean. The green bars show uncertainty estimates. Source: NASA GISS


Observed and expected effects on life 
Over the past 100 years, the global average temperature has increased and projected to continue to rise at a rapid rate. Although species have responded to climatic changes throughout their evolutionary history, a primary concern for wild species and their ecosystems is this rapid rate of change. The gathered information on species and global warming from studies reveal a consistent temperature-related shift, or 'fingerprint', in species ranging from molluscs to mammals and from grasses to trees. Indeed, more than 80% of the species that show changes are shifting in the direction expected on the basis of known physiological constraints of species. Consequently, the balance of evidence from these studies strongly suggests that a significant impact of global warming is already discernible in animal and plant populations. The synergism of rapid temperature rise and other stresses, in particular habitat destruction, could easily disrupt the connectedness among species and lead to a reformulation of species communities, reflecting differential changes in species, and to numerous extirpations and possibly extinctions.
The increase in ocean heat content is much larger than any other store of energy in the Earth’s heat balance over the two periods 1961 to 2003 and 1993 to 2003, and accounts for more than 90% of the possible increase in heat content of the Earth system during these periods.


Observed and expected effects on environment Greenhouse gas, Greenhouse effect, Radiative forcing, and Carbon dioxide in Earth's atmosphere
This graph, known as the Keeling Curve, shows the increase of atmospheric carbon dioxide (CO2) concentrations from 1958–2008. Monthly CO2 measurements display seasonal oscillations in an upward trend; each year's maximum occurs during the Northern Hemisphere's late spring, and declines during its growing season as plants remove some atmospheric CO2.
The 20th century instrumental temperature record shows a sudden rise in global temperatures.

These temperatures are expected to excaberate the hydrological cycle, with more intense droughts and floods.The effect on hurricane activity is less certain. 

Changing monsoon pattern
In the coming time, the consequence of  global warming is going to be severe as monsoon will be delayed after every five years. The prediction of the changing monsoon pattern has been done by Professor Anders Levermann at Climate Impact Research.

Anders Levermann said, "In the past century the Indian monsoon has been very stable. It is already a catastrophe with 10% less rain than the average".


picture source: the hindu.com
The Indian monsoon on which more than a billion people depend for food crops - could fail frequently and catastrophically over the next 200 years as a result of global warming. The researchers define monsoon failure as a drop of between 40 and 70 percent in rainfall, compared with normal levels - something that's never happened in the 140 years of measurements by the India Meteorological Department.

But by 2150, says the Potsdam Institute for Climate Impact Research and Potsdam University team, the rains could be failing every fifth year. India's economy relies heavily on the monsoon season to bring fresh water to farmlands.

"Our study points to the possibility of even more severe changes to monsoon rainfall caused by climatic shifts that may take place later this century and beyond," says lead author Jacob Schewe.
The changes, say the team, would be triggered by increasing temperatures and a change in strength of the Pacific Walker circulation in spring.

The Walker circulation usually brings areas of high pressure to the western Indian Ocean. However, in years when El Niño occurs, this pattern gets shifted eastward, bringing high pressure over India and suppressing the monsoon, especially as it begins to develop in spring.

But the researchers' simulations showed that as temperatures increase in the future, the Walker circulation will bring more high pressure over India - even if El Niño doesn't occur any more often.
*The findings may be controversial, as most models conclude that global warming is more likely to increase monsoon rainfall, rather than decrease it.
  
Do we need a common global strategy !!
About 200 nations have joined hands in reducing the impact of global warming so that natural disasters like draught and flood could be avoided. From 26th of November onwards environment ministries from all over the world will attend a meeting in Qatar. The meeting will be aimed at reducing the global warming impacts.



Climate deal !!
Protecting the world so future generations can enjoy the same benefits requires their rights 
to be expressed now.
Barack Obama speaks at the climate summit in Copenhagen in December 2009. Photograph: Anja Niedringhaus/AP
What does a second term for Barack Obama as US president mean for action on climate change..
The good omens. Climate change was cited in his victory speech, albeit among 2000 other words: "We want our children to live in an America that isn't burdened by debt, that isn't weakened by inequality, that isn't threatened by the destructive power of a warming planet."
  It is a clear advantage to have a president who understands the threat climate change leading the world's biggest historical polluter in the make-or-break year of 2015.
NASA satellite picture of Superstorm Sandy's path of destruction along U.S. East Coast.

Perhaps, chillingly, it will take more searing heatwaves and superstorms to strike to prompt Obama into serious action. But low odds are better than no odds, and that's what a President Romney would have meant (Mitt Romney, whose statement that the president's job was not to stop the sea rising was hideously exposed by the inundation of New York and New Jersey by the surge of superstorm Sandy).

A grim reminder:
Al Gore, Nobel prize acceptance speech, 2007
 We, the human species, are confronting a planetary emergency – a threat to the survival of our civilization that is gathering ominous and destructive potential even as we gather here. But there is hopeful news as well: we have the ability to solve this crisis and avoid the worst – though not all – of its consequences, if we act boldly, decisively and quickly.
Al Gore delivering his Nobel Lecture in the Oslo City Hall, 10 December 2007.
Copyright © The Norwegian Nobel Institute 2007
Photo: Ken Opprann
UNO forum expresses concern over:

United Nations: Secretary-General Ban Ki-moon said that one of the main lessons from Superstorm Sandy is the need for global action to deal with future climate shocks.

Ban told the UN General Assembly that it is difficult to attribute any single storm, like Sandy, to climate change.

 
"But we all know this: extreme weather due to climate change the new normal," he said. "This may be an uncomfortable truth but it is one we ignore at our peril."

With a new round of global climate talks set to begin on November 27 in Doha, Qatar, the UN chief urged the world's nations to reach a legally binding agreement by 2015 to rein in the emissions of heat-trapping gases in order to stop the planet from overheating.
It is the first time a Gulf state has hosted global climate negotiations

*Note: all pictures thankfully shared from various sources..


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