Myths and facts about Global Warming
There is a lot of noise about global warming – some fact and some fiction. Find out if what you know about this phenomenon is true or false.
Myths and facts about Global Warming
MYTH
Life can adapt. Civilization has survived droughts and temperature shifts in the past.
FACT
Humans may have survived the vagaries of drought, stretches of warmth and cold and more, one cannot ignore that entire societies and species have collapsed from dramatic climatic shifts. Remember the mammoth and the dinosaur?
Unless we limit the amount of greenhouse gases that are being released into the atmosphere, the earth will face a warming trend unseen since human civilization began 10,000 years ago. Climate change will bring major hardships and economic dislocations for our future generations.
MYTH
Addressing the problem of climate change will hurt industry and workers of developed economies.
FACT
A well designed trading program can jumpstart a new carbon economy that can decrease heat-trapping pollution cost-effectively.
Companies that are already reducing their greenhouse gas emissions have discovered that cutting pollution can save money. Properly designed emissions trading programs can reduce compliance costs significantly compared with other regulatory approaches. Furthermore, a mandatory cap on emissions could spur technological innovation that could create jobs and wealth.
MYTH
Global warming and extra CO2 will actually be beneficial -- they reduce cold-related deaths and stimulate crop growth.
FACT
Any beneficial effects will be far outweighed by damage and disruption.
Despite the fact that higher levels of CO2 can act as a plant fertilizer under some conditions, scientists now believe that "CO2 fertilization" effect can diminish after a few years as plants acclimatise to it.
Moreover, increasing CO2 levels will cause sea levels to rise and inundate coastal areas and affect large populations across the globe and have devastating effects on marine life and fisheries.
MYTH
Hasn't the Arctic warmed up before? Global warming is just part of a natural cycle.
FACT
What the earth is experiencing today is not natural. The current global warming is caused by mankind.
The Arctic has warmed up before, but then people were not burning fossil fuels (like oil, coal and natural gas) and cutting down forests at the level it is being done today. Human activity is releasing far more CO2 into the atmosphere than was ever released in hundreds of thousands of years.
Natural amounts of CO2 have varied from 180 to 300 parts per million (ppm), but today's CO2 levels are around 380 ppm. That's 25% more than the highest natural levels over the past 650,000 years.
MYTH
Recent cold winters and cool summers don't feel like global warming to me.
FACT
Different parts of the earth have experienced some cold winters here and there, but the overall trend is warmer winters.
"I don't recall any Diwali that I celebrated without wearing a sweater when I was a child," says Tarang Mathur of Delhi. "But now we don't really get into our woollens till December."
Over the last century the Earth's climate has warmed overall, in all seasons, and in most regions. Despite the statements of climate sceptics that "this was the coldest winter in the past 100 years... blah blah blah," a single year of cold weather in one region of the world is not a benchmark for an average trend in global climate.
MYTH
If global warming was actually happening, how come some glaciers and ice sheets are growing, not shrinking?
FACT
In most parts of the world, the retreat of glaciers has been dramatic. The best available scientific data indicate that Greenland's massive ice sheet is shrinking.
Some glaciers in western Norway, Iceland and New Zealand have been expanding over the past few decades, but that expansion is a result of regional increases in storm frequency and snowfall rather than colder temperatures. Between 1961 and 1997, the world's glaciers lost 890 cubic miles of ice.
National Snow and Ice Data Centre states that the summer melting of the Greenland Ice Sheet increased by 30 percent as a result of a warmer climate between 1796 and 2006. The temperature of the Antarctic Peninsula has also increased by 2.5 degrees Celsius since 1950.
MYTH
How can we predict climate projections decades from now accurately when even precise weather predictions a few days in advance are hard to come by?
FACT
Climate prediction is fundamentally different from weather prediction, just as climate is different from weather.
The accuracy of weather forecasting is critically dependent upon being able to exactly and comprehensively characterize the present state of the global atmosphere. Climate prediction relies on other, longer ranging factors.
For instance, we might not know if it will be below freezing on a specific December day in New England, but we know from our understanding of the region's climate that the temperatures during the month will generally be low.
MYTH
As the ozone hole shrinks, global warming will no longer be a problem.
FACT
Global warming and the ozone hole are two different problems.
The ozone layer resides in the stratosphere (9 to 31 miles above the earth's surface) and surrounds the entire Earth, protecting it from the effects of ultraviolet rays. Ozone hole is a thinning of the stratosphere's ozone layer.
Global warming, on the other hand, is the increase in the earth's average temperature due to the buildup of CO2 and other greenhouse gases in the atmosphere from human activities.
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