Investigation of The Consequences of Climate Change

The Birth of the Greenhouse Effect Theory

In 1896, the Swedish scientist Svante Arrhenius introduced a groundbreaking idea: when humans burned fossil fuels such as coal, it would increase the planet’s average temperature by adding carbon dioxide to the Earth’s atmosphere. This phenomenon, known as the “greenhouse effect,” was just one of many theories regarding climate change, but it was not initially considered the most logical. Many scientists argued that these emissions could not alter the climate, with the prevailing belief being that humanity, on such a small scale, could never affect something as vast as climate cycles (Arrhenius, 1896).

Early Observations and Skepticism

Ice ages in the past demonstrated that climate could change drastically across the entire planet, a change that seemed far beyond human provocation. In the 1930s, it was observed that the United States and the North Atlantic region had warmed significantly over the previous half-century. Scientists believed this was merely a phase of a mild natural cycle. Only the amateur scientist G. S. Callendar insisted that greenhouse warming was occurring. By the 1950s, Callendar’s claims had prompted some scientists to investigate further. New studies indicated that carbon dioxide could indeed accumulate in the atmosphere and contribute to warming (Callendar, 1938).

Growing Evidence and Public Awareness

By 1960, evidence began to emerge that the level of carbon dioxide was rising year by year, opening people’s eyes to the potential issue. Researchers found methods to reconstruct past temperatures by analyzing ancient pollens and fossil shells. It appeared that climate change could occur, and had occurred, within just a few centuries (Revelle & Suess, 1957). In the early 1970s, environmentalism's rise fueled public doubts about the positive effects humans were having on the planet, and curiosity soon turned into concern. Alongside the greenhouse effect, some scientists pointed out that human activity was introducing dust and smog particles into the atmosphere, potentially blocking sunlight and causing global cooling. This was supported by an analysis of Northern Hemisphere weather statistics showing a cooling trend that had begun in the 1940s (Bryson, 1974).

Shifting Focus to Global Warming

After a few years, the warnings of a new ice age were dismissed as only a minority of scientists supported this theory. Attention shifted to global warming. Evidence of significant temperature changes was uncovered when the Greenland ice sheet was drilled, revealing abrupt shifts. Advanced computer models began to suggest mechanisms for such temperature changes, such as alterations in ocean currents' circulation. Experts predicted droughts, storms, rising sea levels, and other disasters resulting from global warming (Hansen et al., 1981).

Unanticipated Discoveries and Public Concern

One unexpected discovery was the rise in methane and certain other gases, which would significantly contribute to global warming. Some of these gases also degraded the atmosphere’s protective ozone layer, inflaming public worries about atmospheric fragility. By the late 1970s, global temperatures had begun to rise again, and public concern was reignited when the summer of 1988 became the hottest on record at that time (Rowland & Molina, 1974).

Challenges in Climate Modeling

Scientists didn’t fully comprehend the effects of pollution on the climate and the processes involved, making it difficult to persuade skeptics. Only improved observations and computer models could attempt to project future outcomes. The physics of clouds and pollution remained complex, and scientists with different theories arrived at varying results. Most predicted a warming of around 3°C when carbon dioxide levels doubled by the late 21st century. Some estimated a rise of 2°C or slightly less, which would be costly but manageable, while others projected a 5°C increase or more, potentially catastrophic (IPCC, 2001).

International Response and Current Understanding

A panel was created by governments worldwide to provide the most reliable advice available at the time. Negotiated among thousands of expert climate scientists and officials, the Intergovernmental Panel on Climate Change (IPCC) produced a written agreement by 2001. They announced that, although the climate system was complex and scientists would never achieve complete certainty, it was much more likely than not that our civilization faced severe global warming. By then, scientists understood the most critical aspects of how the climate could change during the 21st century and how it would change, depending solely on humanity's actions regarding greenhouse gas emissions (IPCC, 2001).

Current Developments and Future Challenges

Climate scientists experienced both positive and negative results. On the positive side, a dangerous change in ocean circulation seemed unlikely in the next century or two. However, signs indicated that disintegrating ice sheets could raise sea levels faster than most scientists had anticipated. Worse still, new evidence suggested that warming was beginning to cause changes that would generate further warming. These developments underscore the urgency of addressing climate change proactively (Rahmstorf, 2007).

References:

Arrhenius, S. (1896). On the Influence of Carbonic Acid in the Air upon the Temperature of the Ground. Philosophical Magazine and Journal of Science, 41, 237-276.

Callendar, G. S. (1938). The Artificial Production of Carbon Dioxide and its Influence on Temperature. Quarterly Journal of the Royal Meteorological Society, 64(275), 223-240.

Revelle, R., & Suess, H. E. (1957). Carbon Dioxide Exchange Between Atmosphere and Ocean and the Question of an Increase of Atmospheric CO2 During the Past Decades. Tellus, 9(1), 18-27.

Bryson, R. A. (1974). A Perspective on Climatic Change. Science, 184(4138), 753-760.

Hansen, J., Johnson, D., Lacis, A., Lebedeff, S., Lee, P., Rind, D., & Russell, G. (1981). Climate Impact of Increasing Atmospheric Carbon Dioxide. Science, 213(4511), 957-966.

Rowland, F. S., & Molina, M. J. (1974). Stratospheric Sink for Chlorofluoromethanes: Chlorine Atom-Catalysed Destruction of Ozone. Nature, 249(5460), 810-812.

IPCC. (2001). Climate Change 2001: Synthesis Report. Cambridge University Press.

Rahmstorf, S. (2007). A Semi-Empirical Approach to Projecting Future Sea-Level Rise. Science, 315(5810), 368-370.