Investigation of The Consequences of Climate Change

In 1896 the Swedish scientist Svante Arrhenius published a new idea which was when humans burned fossil fuels such as coal, this would raise the planet’s average temperature, as it added carbon dioxide into the Earth’s atmosphere. This “greenhouse effect” was only one of many theories about climate change, but not the most logical. Scientists found reasons to argue that these emissions could not change the climate, the main belief being that humanity, on such a small scale could never have any effect on something so vast as the climate cycles.

Ice ages in the past proved that climate could change radically over the entire planet, which seemed beyond anything that humanity could provoke. In the 1930s, people realized that the United States and North Atlantic region had warmed significantly during the previous half-century which scientists thought was just a phase of some mild natural cycle. Only the amateur G. S. Callendar, insisted that greenhouse warming was happening. In the 1950s, Callendar’s claims prompted a few scientists to look into the subject and the new studies showed that carbon dioxide could indeed build up in the atmosphere and should bring warming. In 1960, evidence that the level of the gas was rising year by year was beginning to open people’s eyes to the issue. Others figured out ways to retrieve past temperatures by studying ancient pollens and fossil shells. It appeared that climate change could happen, and in the past had happened, within as little as a few centuries.

In the early 1970s, the rise of environmentalism fuelled public doubts about the positive effects humans were having on the planet. Curiosity soon turned into concern. Alongside the greenhouse effect, some scientists pointed out that human activity was putting dust and smog particles into the atmosphere, where they could block sunlight and cause the planet to decrease in temperature, which was supported by an analysis of Northern Hemisphere weather statistics showing a cooling trend that had begun in the 1940s.

After a few years, the warnings of a new ice age were dropped as only a few scientists supported this theory, and attention now turned to global warming. Evidence of huge temperature changes was shown when the Greenland ice sheet was drilled, and abrupt ones at that. Vastly improved computer models began to suggest how such huge temperature changes could occur, for example through a change in the circulation of ocean currents. Experts predicted droughts, storms, rising sea levels, and other disasters from global warming.

One unexpected discovery was that the level of methane and certain other gases was rising, which would add seriously to global warming. Some of these gases also degraded the atmosphere’s protective ozone layer, and the news inflamed public worries about the fragility of the atmosphere. Moreover, by the late 1970s, global temperatures had begun to rise again and the public began to worry again when summer of 1988 came about, which was the hottest on record till then.

Scientists didn’t fully understand the effect of pollution on the climate and the processes involved yet, so it was difficult to persuade the people who opposed and doubted this theory. Only better observations and computer models could attempt to project the outcome.

The physics of clouds and pollution remained too complex to work out exactly, and scientists with different theories ended up with different results. Most of them found a warming of around 3°C when the carbon dioxide level doubled, late in the 21st century. But some found a rise of 2°C or slightly less, which would be costly but manageable. Others calculated a 5°C rise or even more, which would lead to a catastrophe.

A panel was created by the governments in the world panel which gave the most reliable advice available at the time. This was negotiated among thousands of expert climate scientists and officials and by 2001 this Intergovernmental Panel on Climate Change (IPCC) managed to produce a written agreement. They announced that although the climate system was so complex that scientists would never reach complete certainty, it was much more likely than not that our civilization faced severe global warming. At that point, scientists knew the most important things about how the climate could change during the 21st century and how the climate would change now, depending solely on how humanity decided to alter the mass emission of greenhouse gases.

Climate scientist was experiencing positive and negative results. The positive in being that a dangerous change in ocean circulation seemed unlikely in the next century or two. The negative being that there were signs that disintegrating ice sheets could raise sea levels faster than most scientists had expected. Worse still, new evidence suggested that the warming was itself starting to cause changes that would generate more warming.