Global Warming

OVERVIEW

Climate change is a change in the pattern of weather, and related changes in oceans, land surfaces and ice sheets,occurring over time scales of decades or longer

Weather is the state of the atmosphere—its temperature, humidity, wind, rainfall and so on—over hours to weeks.

It is influenced by the oceans, land surfaces and ice sheets, which together with the atmosphere form what is called the ‘climate system’. Climate, in its broadest sense, is the statistical description of the state of the climate system.

Climate change is a change in the statistical properties of the climate system that persists for several decades or longer—usually at least 30 years. These statistical properties include averages, variability and extremes. Climate change may be due to natural processes, such as changes in the Sun’s radiation, volcanoes or internal variability in the climate system, or due to human influences such as changes in the composition of the atmosphere or land use.

Weather can be forecast with considerable skill up to about a week in advance. Short term fluctuations in climate,such as droughts, can be predicted with limited skill from season to season. In contrast, changes in the long-term statistics of the climate system (climate change) can be predicted if caused by long-term influences that are knownor predictable.

Cause

Greenhouses gases, such as carbon dioxide, trap heat in the atmosphere and regulate our climate. These gases exist naturally, but humans add more carbon dioxide by burning fossil fuels for energy (coal, oil, and natural gas) and by clearing forests. Greenhouse gases act like a blanket. The thicker the blanket, the warmer our planet becomes. At the same time, the Earth’s oceans are also absorbing some of this extra carbon dioxide, making them more acidic and less hospitable for sea life. The increase in global temperature is significantly altering our planet’s climate, resulting in more extreme and unpredictable weather. For instance, heat waves are becoming more frequent and many places are experiencing record droughts followed by intense rainfalls.

SCIENTISTS AGREE, HUMANS CAUSE CLIMATE CHANGE

Scientists in the United States and the world have reached an overwhelming consensus that climate change is real and caused primarily by human activity. Respected scientific organizations such as the National Academy of Science, the Intergovernmental Panel on Climate Change (IPCC) and World Meteorological Association (WMO) have all identified climate change as an urgent threat caused by humans that must be addressed. “The need for urgent action to address climate change is now indisputable.”

FOSSIL FUELS

Fossil fuels, such as coal ,oil and natural gas , to generate energy has the greatest impact on the atmosphere than any other single human activity. Globally, power generation is responsible for about 23 billion tonnes of CO2 emissions per year – in excess of 700 tonnes every second. Coal is especially damaging to our atmosphere, releasing 70% more carbon dioxide than natural gas for every unit of energy produced.

Car pollution is one of the major causes of global warming. Cars and trucks emit carbon dioxide and other greenhouse gases, which contribute one-fifth of the United States' total global warming pollution. Greenhouse gases trap heat in the atmosphere, which causes worldwide temperatures to rise. Without greenhouse gases, the Earth would be covered in ice, but burning excessive amounts of fossil fuels, such as gasoline and diesel, has caused an increase of 0.6 degrees Celsius, or 1 degree F, in global temperatures since pre-industrial times, and this will continue to rise over the coming decades. Warmer global temperatures affect farming, wildlife, sea levels and natural landscapes.

The effects of car pollution are widespread, affecting air, soil and water quality. Nitrous oxide contributes to the depletion of the ozone layer, which shields the Earth from harmful ultraviolet radiation from the sun. Sulfur dioxide and nitrogen dioxide mix with rainwater to create acid rain, which damages crops, forests and other vegetation and buildings. Oil and fuel spills from cars and trucks seep into the soil near highways, and discarded fuel and particulates from vehicle emissions contaminate lakes, rivers and wetlands.

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Deforestation & Tree-Clearing

From logging, agricultural production and other economic activities, deforestation adds more atmospheric CO2 than the sum total of cars and trucks on the world's roads.

By most accounts, deforestation in tropical rainforests adds more carbon dioxide to the atmosphere than the sum total of cars and trucks on the world’s roads. According to the World Carfree Network (WCN), cars and trucks account for about 14 percent of global carbon emissions, while most analysts attribute upwards of 15 percent to deforestation.

The reason that logging is so bad for the climate is that when trees are felled they release the carbon they are storing into the atmosphere, where it mingles with greenhouse gases from other sources and contributes to global warming accordingly. The upshot is that we should be doing as much to prevent deforestation as we are to increase fuel efficiency and reduce automobile usage.

According to the Environmental Defense Fund (EDF), a leading green group, 32 million acres of tropical rainforest were cut down each year between 2000 and 2009—and the pace of deforestation is only increasing. “Unless we change the present system that rewards forest destruction, forest clearing will put another 200 billion tons of carbon into the atmosphere in coming decades…,” says EDF.

“Any realistic plan to reduce global warming pollution sufficiently—and in time—to avoid dangerous consequences must rely in part on preserving tropical forests,” reports EDF. But it’s hard to convince the poor residents of the Amazon basin and other tropical regions of the world to stop cutting down trees when the forests are still worth more dead than alive. “Conservation costs money, while profits from timber, charcoal, pasture and cropland drive people to cut down forests,” adds EDF. Exacerbating global warming isn’t the only negative impact of tropical deforestation. It also wipes out biodiversity: More than half of the world’s plant and animal species live in tropical rainforests.

One way some tropical countries are reducing deforestation is through participation in the United Nations’ Reducing Emissions from Deforestation and Forest Degradation(REDD) program. REDD essentially works to establish incentives for the people who care for the forest to manage it sustainably while still being able to benefit economically. Examples include using less land (and therefore cutting fewer trees) for activities such as coffee growing and meat and milk production. Participating nations can then accrue and sell carbon pollution credits when they can prove they have lowered deforestation below a baseline. The REDD program has channeled over $117 million in direct financial aid and educational support into national deforestation reduction efforts in 44 developing countries across Africa, Asia and Latin America since its 2008 inception.

Brazil is among the countries embracing REDD among other efforts to reduce carbon emissions. Thanks to the program,Brazil has slowed deforestation within its borders by 40 percent since 2008 and is on track to achieve an 80 percent reduction by 2020. Environmentalists are optimistic that the initial success of REDD in Brazil bodes well for reducing deforestation in other parts of the tropics as well.

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Ways to Stop Global Warming

Reduce Fossil Fuel Use

Burning fossil fuels increases the levels of greenhouse gases in the atmosphere. There are two ways to reduce fossil fuel use: Use less energy, or use alternative, nonpolluting energy sources like solar and wind power. At home, this translates to saving electricity by using energy-efficient appliances and compact fluorescent light bulbs, as well as reducing gasoline use and buying green power from your electricity provider, if available

Plant Trees

Because carbon dioxide is the most important greenhouse gas, planting trees and other plants can slow or stop global warming. Plants take in carbon dioxide and release oxygen. They use carbon to build their own tissues and return some of it to the soil in a process called sequestration. Deforestation of rain forests is a large contributor to global warming and CO2 emissions, but planting new trees, even in your own backyard, can help to offset this.

Help the planet

Plant a tree

Reduce Waste

The production of garbage contributes to global warming both directly and indirectly. Decomposing waste in landfills produces methane and other greenhouse gases. Waste also requires energy to manufacture in the first place. Reducing your consumption patterns and reusing items whenever possible minimizes your carbon footprint, since fewer new items need to be made. Recycling metal, plastic, glass and paper lowers greenhouse gas emissions, since recycled items take far less energy to manufacture than items produced from scratch.

Conserve Water

Cities consume significant amounts of energy when purifying and distributing water, which contributes to greenhouse gas emissions. Saving water reduces the amount of energy used. At home, turn off water immediately whenever you're not using it, and repair or replace leaky faucets and toilets. In your yard, landscape with plants and grasses that require less water, and capture rainwater in barrels for irrigating.