Global warming is a theory that seeks to pinpoint and explain the Earth's recent and successive increases in temperature. A considerable number of scientists believe that this warming is related to human action on the nature, causing devastating effects on it, such as the destruction of the ozone layer and the intensification of Greenhouse effect.
For many scientists, the Global warming it is no longer treated as a theory, but as a phenomenon. It is estimated that in the last century, temperatures have risen by an average of 0.7°C and that in the next century, thermal increases will fluctuate between 1.6°C and 4°C. The IPCC (Intergovernmental Panel on Climate Change), a scientific body linked to the United Nations (UN), records that most of the temperature increases in the last century occurred between the 1980s and 2005. The agency also points out that the last years of the 1990s recorded the highest average temperature in history.
The causes of Global Warming have not yet been fully explained. But the main ones concern the rates of emission of polluting gases into the atmosphere. Another factor would be the destruction of forests around the world, which would have the function of increasing the amount of moisture in the atmosphere, which would be a favorable factor for lowering temperatures.
Through the IPCC, the UN advocates the idea that it is necessary to reduce by 90% the current emissions of called "greenhouse gases", which would be the protagonists of the process of increasing the temperatures of planets. In addition, the organization also defends the importance of conserving natural resources, especially plant formations.
The effects of Global Warming are very varied. The main fanfare revolves around the rise in sea level, which is said to be caused by the increasing melting of the polar ice caps. Another factor worth mentioning is the increase in cyclical natural phenomena, such as El Niño and La Niña. Scientists claim that these are occurring at increasingly shorter time intervals, causing climate change in terms of rainfall, humidity variation, among others.
Greenhouse Gases
Currently, six gases are on the world's "black list", identified as the main responsible for global warming: Methane (CH4), Carbon Dioxide (CO2), Nitrous Oxide (N2O), Hydrofluorocarbon (HFC), Chlorofluorocarbon (CFC) and Sulfur Hexafluoride (SF6).
Among these gases, the one that currently has the greatest interference on rising temperatures is CO2, with 70% weight on global warming, according to some estimates. However, this is not the most potentially harmful gas on the list, but SF6, which is considered thousands of times more potent than Carbon Dioxide and which only does not interfere more than it for the Greenhouse Effect due to its current low emission levels.
The greenhouse effect is a natural phenomenon, which exists to maintain the Earth's natural warming. Without it, temperatures would be very low, which would make it difficult for
life on the planet. However, the aforementioned gases intensify the process of keeping heat in our atmosphere, causing an exaggerated increase in temperatures, which can also have dire effects on the environment in that we live.
Global Warming does not exist, scientists point out
As we have stated before, Global Warming is no longer considered a simple theory for some scientists, but a fact. However, this position is not a consensus in the academic world, with an increasing current of researchers reluctant to consider the existence of rising temperatures as a consequence of the action human.
The central assertion of disputes about the existence of Global Warming is that the Greenhouse Effect does not exist or that it does not exert as much influence on the Earth's temperature. For these scientists, what really determines the Earth's temperature is not the process of reflection of the sun's rays on the atmosphere, but the heat of the Sun.
The temperature of the oceans, in turn, would also be one of the main determining elements. That's because they make up nearly 3/4 of the Earth's surface. Consequently, their temperature variations will interfere with climate variations and the amount of moisture in the atmosphere.
Another question refers to the responsibility of the CO2 on the retention of heat in the environment. This is because its rate of rise in the atmosphere would be less than 1% of atmospheric gases, in addition to its rise rate it would not yet have been proven, as measurements carried out on Earth would not be endorsed by those carried out by satellites.
Regarding the melting of glaciers, the researchers claim that only those ice caps that are already over the oceans are in the melting phase. Thus, its change in physical state does not cause an increase in the volume of water. To understand, just look at the experience of the glass of water with ice cubes that, when melted, do not raise the water level in the glass, since the ice is already part of the total volume.
One of the central issues in the controversy is the consequences of melting glaciers
Furthermore, the increase in the occurrence of phenomena such as El Niño and La Niña is also not a consensus. Some scientists relate this occurrence to the Pacific Decadal Oscillation, a cycle of varying water temperatures in the Pacific Ocean – the largest in the world – that occurs every twenty years. In times of rising temperatures, the occurrence of El Niño would increase; in time of decrease, the occurrence of La Niña would increase.
Therefore, we can observe that Global Warming is not a fully proven fact, however its non-existence cannot yet be put as a certainty. In addition, it is necessary to remember that the emission of polluting gases and the deforestation of forests must not continue. This is because the environmental consequences can be of different orders, such as interference in urban microclimates (such as the Heat Islands) and the extinction of animal and plant species.
By Me. Rodolfo Alves Pena
Source: Brazil School - https://brasilescola.uol.com.br/o-que-e/geografia/o-que-e-aquecimento-global.htm
