globalwarming awareness2007

globalwarming awareness2007

Primary Review (Christopher Haas)
The article discussed some of the different aspects of global warming that most scientists

studying the phenomenon tend to agree upon.   It also explored the different tools

used by scientists to research global warming and the different information obtained.  The article discussed numerous findings, generally agreed upon by scientists,

supporting the theory of an “enhanced greenhouse effect”. 

It is customarily agreed that the average global air temperature has risen 0.3 to 0.6 degrees Celsius over the past century. 

The rise in global temperature is supported by indicators such as an increased rate of the melting of alpine glaciers and a rise in sea level near the magnitude of 10 to 25 cm in the past one hundred years. 

Previous articles indicated the average global temperatures have been highest in the past decade, and the present article as well stated the average global temperature in 1995 was to be as high or higher than any previous years since the beginning of accurate temperature recordings in 1860. 

The experts also agree that the nighttime temperatures have increased more than daytime temperatures, and unless greenhouse gas emission is reduced by a large quantity the average globalwarming awareness2007 temperature will increase 1 to 3.5 degrees Celsius during the next century due to the expected doubling in CO2 levels between 2050 and 2100. 

 Overall scientists believe that an increase in global temperature within the next century will cause more frequent and intense heat waves, widescale ecological disruptions, a decline of agricultural production in the tropics and subtropics, and continued increases in the rate of sea level rise.  Greenhouse gases, especially CO2, have increased in concentration in the atmosphere significantly since preindustrial times.  CO2 has risen an estimated 30% and methane 145%.  Previous articles estimated similar levels. 

It is also broadly agreed that a loss of ozone and an increase in aerosols would have a cooling effect on the earth. 

The effect, however, would be canceled out by the expected doubling of the CO2 level predicted for the future.  The short life span of aerosols, generally two weeks, as compared to the long life span of greenhouse gases like CO2 and water, decreases their combative effect on global warming.
Computer modeling of global climate change was also discussed in the article. 

Atmospheric and ocean models are used to produce climate features of the past and in turn predict future climate changes.

Secondary Review (Elizabeth Jones)
  According to the authors, globalwarming awareness2007 despite the seeming controversy surrounding the reality of global warming, most researchers can come to a consensus regarding certain key points.

First, most researchers agree that the Earth’s climate is already experiencing the effects of global warming due to human activity. As evidence, the authors site the accelerated melting of alpine glaciers, the rise in sea level of 10-25 cm, coral bleaching caused by unusually high sea-surface temperatures, and the drastic increase since pre-industrial times of greenhouse gases present in the atmosphere.

 Carbon dioxide, methane, and nitrous oxide have risen 30%, 145%, and 15% respectively. They then state that without drastic steps, the average global temperature will increase 1-3.5? C during the next century. These higher temperatures will cause more intense and more frequent heat waves, ecological disruptions, a decline in agricultural production in the tropics and sub-tropics, and the continued acceleration of the rising of the sea level.

Another area in which experts agree is that stratospheric ozone depletion and aerosols act to cool the Earth. Unlike greenhouse gases, however, the depletion of the ozone does not cause a uniform global cooling, it instead affects the climate pattern on a subcontinental level. 

Although aerosols act to cool the earth, they have a very short life span so they do not build up in the environment as much as greenhouse gasses; therefore the cooling effect that does occur cannot offset the warming from greenhouse gases.

GLOBAL TEMPERATURE NEAR RECORD FOR 2002
Takes Toll in Deadly Heat Waves, Withered Harvests, and Melting Ice

Lester R. Brown

Temperature data for the first 11 months of 2002 indicate that this year will likely be the second warmest on record, exceeded only by 1998. These data from the Goddard Institute for Space Studies indicate that globalwarming awareness2007 the temperature for the first 11 months has averaged 14.65 degrees Celsius (58.37 degrees Fahrenheit), down slightly from the record high of 14.69 in 1998, but well above the average temperature of 14 degrees Celsius that prevailed from 1951 to 1980.
Studying these annual temperature data, globalwarming one gets the unmistakable feeling that temperature is rising and that the rise is gaining momentum.

 A year ago, we noted that the 15 warmest years since recordkeeping began in 1867 had occurred since 1980. Barring a dramatic drop in temperature for December, we can now say that the three warmest years on record have come in the last five years.
In addition to the longer-term annual temperature trend, recent monthly data also indicate an accelerating rise.

In contrast to local temperatures, which fluctuate widely from season to season, the global average temperature is remarkably stable throughout the year because the seasonal contrasts of the northern and southern hemispheres offset each other awareness2007.

 The temperature for January of this year of 14.72 degrees Celsius was the highest on record for January. The 14.91 degrees for March made it the warmest March on record.

And in seven of the next eight months—April through November—the temperature was either the second or the third warmest.

October was the fourth warmest.