Many Groups Organize Measures Against Global Warming

Many Groups Organize Measures Against Global Warming

Although there is much evidence that global warming is the result of human activity, this evidence is not completely accepted by all of the experts. The evidence does not have to be positive in order to take positive steps against global warming. There are many steps to take against global warming. First of all, people can work to reduce the use of fossil fuels including gasoline in their cars. People can join a carpool so they are not driving alone in their car. There are now fuel efficient cars that conserve on the fuel used to get any distance. More people should try to drive these cars that use less fuel. The companies that manufacture cars should concentrate on making cars that are more fuel efficient.

People can try to use alternative means to heat their water and their homes during the winter. Solar energy is from a renewable source of energy so people should try to use these alternatives if possible. People should try to recycle paper for these efforts could make a significant difference to the environment. People should try to make sure that their public servants in charge of the forests are replacing the trees that are taken from the forest.

Positive Actions Against Global warming

Positive Actions Against Global warming

Many people and their elected officials are taking positive steps against global warming so the world will be a better place for their children and grandchildren. There is a great deal of information on the effects of global warming, and the experts on the subject have provided positive steps that people can make against global warming. Scientists have studied the progress of global warming, and some of these scientists have come up with information on the problem to keep the public informed. Along with the information on the problem, these experts have also outlined the steps that people can take to work against global warming.

Global warming seems to be a problem, and the facts show that the temperatures are rising every year since the records were first kept sometime in the middle of the nineteenth century. The problem seems to be getting worse every year. Glaciers seem to be melting more rapidly, and the snow seems to be less every year. There also seems to be a rise in the level of the sea. This is particularly frightening because some of the populated land could one day become completely submerged. Many scientists now believe that these changes in the world are the result of human activity.

Greenhouse gases

The greenhouse effect is the process by which absorption and emission of infrared radiation by gases in the atmosphere warm a planet's lower atmosphere and surface. It was discovered by Joseph Fourier in 1824 and was first investigated quantitatively by Svante Arrhenius in 1896. Existence of the greenhouse effect as such is not disputed, even by those who do not agree that the recent temperature increase is attributable to human activity. The question is instead how the strength of the greenhouse effect changes when human activity increases the concentrations of greenhouse gases in the atmosphere.

Naturally occurring greenhouse gases have a mean warming effect of about 33 °C (59 °F). The major greenhouse gases are water vapor, which causes about 36–70 percent of the greenhouse effect; carbon dioxide (CO₂), which causes 9–26 percent; methane (CH₄), which causes 4–9 percent; and ozone (O₃), which causes 3–7 percent. Clouds also affect the radiation balance, but they are composed of liquid water or ice and so are considered separately from water vapor and other gases.

Human activity since the Industrial Revolution has increased the amount of greenhouse gases in the atmosphere, leading to increased radiative forcing from CO₂, methane, tropospheric ozone, CFCs and nitrous oxide. The concentrations of CO₂ and methane have increased by 36% and 148% respectively since 1750. These levels are much higher than at any time during the last 650,000 years, the period for which reliable data has been extracted from ice cores. Less direct geological evidence indicates that CO₂ values higher than this were last seen about 20 million years ago. Fossil fuel burning has produced about three-quarters of the increase in CO₂ from human activity over the past 20 years. Most of the rest is due to land-use change, particularly deforestation.

CO₂ concentrations are continuing to rise due to burning of fossil fuels and land-use change. The future rate of rise will depend on uncertain economic, sociological, technological, and natural developments. Accordingly, the IPCC Special Report on Emissions Scenarios gives a wide range of future CO₂ scenarios, ranging from 541 to 970 ppm by the year 2100 (an increase by 90-250% since 1750). Fossil fuel reserves are sufficient to reach these levels and continue emissions past 2100 if coal,tar sands or methane clathrates are extensively exploited.

The destruction of stratospheric ozone by chlorofluorocarbonsis sometimes mentioned in relation to global warming. Although there are a few areas of linkage, the relationship between the two is not strong. Reduction of stratospheric ozone has a cooling influence, but substantial ozone depletion did not occur until the late 1970s. Ozone in the troposphere (the lowest part of the Earth's atmosphere) does contribute to surface warming.

Temperature changes

The most common measure of global warming is the trend in globally averaged temperature near the Earth's surface. Expressed as a linear trend, this temperature rose by 0.74 ± 0.18 °C over the period 1906–2005. The rate of warming over the last half of that period was almost double that for the period as a whole (0.13 ± 0.03 °C per decade, versus 0.07 °C ± 0.02 °C per decade). The urban heat island effect is estimated to account for about 0.002 °C of warming per decade since 1900. Temperatures in the lower troposphere have increased between 0.13 and 0.22 °C (0.22 and 0.4 °F) per decade since 1979, according to satellite temperature measurements. Temperature is believed to have been relatively stable over the one or tw0 thousand years before 1850, with regionally varying fluctuations such as the Medieval Warm Period and the Little Ice Age. Estimates by NASA's Goddard Institute for Space Studies and the National Climatic Data Center show that 2005 was the warmest year since reliable, widespread instrumental measurements became available in the late 1800s, exceeding the previous record set in 1998 by a few hundredths of a degree. Estimates prepared by the World Meteorological Organization and the Climatic Research Unit show 2005 as the second warmest year, behind 1998. Temperatures in 1998 were unusually warm because the strongest El Nino in the past century occurred during that year. Global temperature is subject to short-term fluctuations that overlay long term trends and can temporarily mask them. The relative stability in temperature from 2002 to 2009 is consistent with such an episode.

Temperature changes vary over the globe. Since 1979, land temperatures have increased about twice as fast as ocean temperatures (0.25 °C per decade against 0.13 °C per decade). Ocean temperatures increase more slowly than land temperatures because of the larger effective heat capacity of the oceans and because the ocean loses more heat by evaporation. The Northern Hemisphere warms faster than the Southern Hemisphere because it has more land and because it has extensive areas of seasonal snow and sea-ice cover subject to ice-albedo feedback. Although more greenhouse gases are emitted in the Northern than Southern Hemisphere this does not contribute to the difference in warming because the major greenhouse gases persist long enough to mix between hemispheres.

The thermal inertia of the oceans and slow responses of other indirect effects mean that climate can take centuries or longer to adjust to changes in forcing. Climate commitment studies indicate that even if greenhouse gases were stabilized at 2000 levels, a further warming of about 0.5 °C (0.9 °F) would still occur.

Global Warming Likely to Significantly Affect Rainfall Patterns

Climate models project that the global average temperature will rise about 1°C by the middle of the century, if we continue with business as usual and emit greenhouse gases as we have been. The global average, though, does not tell us anything about what will happen to regional climates, for example rainfall in the western United States or in paradisical islands like Hawai'i. Analyzing global model warming projections in models used by the Intergovernmental Panel on Climate Change, a team of scientists headed by meteorologist Shang-Ping Xie at the University of Hawaii at Monoa's International Pacific Research Center, finds that ocean temperature patterns in the tropics and subtropics will change in ways that will lead to significant changes in rainfall patterns. The study will be published in the Journal of Climate this month, breaking ground on such regional climate forecasts.
Scientists have mostly assumed that the surfaces of Earth's oceans will warm rather evenly in the tropics. This assumption has led to "wetter-gets-wetter" and "drier-gets-drier" regional rainfall projections. Xie's team has gathered evidence that, although ocean surface temperatures can be expected to increase mostly everywhere by the middle of the century, the increase may differ by up to 1.5°C depending upon the region.
"Compared to the mean projected rise of 1°C, such differences are fairly large and can have a pronounced impact on tropical and subtropical climate by altering atmospheric heating patterns and therefore rainfall," explains Xie. "Our results broadly indicate that regions of peak sea surface temperature will get wetter, and those relatively cool will get drier."
Two patterns stand out. First, the maximum temperature rise in the Pacific is along a broad band at the equator. Already today the equatorial Pacific sets the rhythm of a global climate oscillation as shown by the world-wide impact of El Niño. This broad band of peak temperature on the equator changes the atmospheric heating in the models. By anchoring a rainband similar to that during an El Nino, it influences climate around the world through atmospheric tele connections. A second ocean warming pattern with major impact on rainfall noted by Xie and his colleagues occurs in the Indian Ocean and would affect the lives of billions of people. Overlayed on Indian Ocean warming for part of the year is what scientists call the Indian Ocean Dipole that occasionally occurs today once every decade or so. Thus, the models show that warming in the western Indian Ocean is amplified, reaching 1.5°C, while the eastern Indian Ocean it is dampened to around 0.5°C. "Should this pattern come about," Xie predicts, "it can be expected to dramatically shift rainfall over eastern Africa, India, and Southeast Asia. Droughts could then beset Indonesia and Australia, whereas regions of India and regions of Africa bordering the Arabian Sea could get more rain than today."
Patterns of sea surface temperature warming and precipitation change in 2050 as compared with 2000. Annual mean precipitation change is shown in green/gray shade and white contours in mm/month. Precipitation tends to increase over regions with ocean warming above the tropical mean and to decrease where ocean warming is below the tropical mean (contours of cool colors).

Rising Sea Levels: Environmental Impact

I discuss the ways in which rising tides can decimate local ecosystems and the environment.
One of the most discussed effects of global warming is the increased rate of sea level rise. The rise is due primarily to higher temperatures, which effect sea levels in two ways. First, if temperatures rise, water gets hotter, causing it to expand. Second, the heat melts ice sheets, caps, and glaciers, causing melt water to flow into the oceans. In a previous article, I discussed the impact of sea level rise on humans; in this article, I will discuss the impact on the environment.

Land Loss
Coastal wetlands are key ecosystems in the biosphere. They support a combination of oceanic species and land species- everything from seagulls to striped bass. They form a “transition zone”, where salt and freshwater fish species like the trout can pass from rivers and streams to the sea. However, rising sea levels are threatening these key habitats. As ocean levels rise, erosion occurs on the shore. As wetlands depend on solid ground for cattails and other aquatic plants to grow, the removal of earth can be devastating. Researchers suggest that by 2080 almost 33% of wetlands will be converted into open water.

Water Salinity
Most aquatic animal and plant species are highly sensitive to salinity levels in their water. As sea levels rise, they flood low-lying freshwater marshes and lakes, making them partially saline. This can kill and damage many native species. The Florida Everglades, for example, are in danger of become salty due to the encroachment of the Atlantic ocean. This would devastate the rich plant and animal life of the Everglades.

Storms
Rising sea levels increase the intensity of storms and floods throughout the world. In high-risk areas like Southeast Asia and Australia, floods could decimate much of the inland plant and animal population. Most ground and burrowing animals, for example, could drown in their dens. Australian researchers have modeled the effects of floods in the future and have discovered that, with the current rate of sea level rise, a storm that now floods 32 square kilometers will flood 71 square kilometers by 2050. So even though sea levels rise only a few millimeters per year, they can have disastrous effects on world ecosystems. It shows just how sensitive nature is- the smallest change can make a world of difference.