The planet's global temperature has risen 1.2 °C since 1880, and the change in the land surface has been more intense than in the seas and much greater at the poles than in the tropics. Almost all climate scientists argue that this increase is caused by human activity, stating the following arguments:
1. The earth has always had climatic cycles but the increase in greenhouse gases since the beginning of the Industrial Revolution has been a hundred times faster than during natural processes in the past. The current level of CO2 stands at 420 parts per million, the highest in 3 million years when the global temperature was at that time 2.5 °C warmer and sea level 20 meters higher than today.
2. Cyclical solar activity is not responsible for this warming because it has actually decreased in the second half of the 20th century. As a proof, the higher layers of the atmosphere have cooled while those closest to the surface, those that are exposed to greenhouse gases, have warmed.
3. The carbon (C) has three sub-classifications called 12, 13 and 14. The 12 is the result of burning fossil fuels and is the one that has become more prevalent in the atmosphere. Fossil fuels like coal and oil contain carbon that has been absorbed for millions of years.
The combustion of these gases is mixing with all ecosystems causing that:
1. The acidification of the seas has increased 30% compared to the beginning of the 20th century, thus threatening the diversity of marine life.
2. Heat waves are seven times more frequent, and maximum temperature records are twice as high as those for cold ones since 1950.
3. The polar caps and glaciers have lost an enormous amount of mass. At this rate, the ice present in the Arctic during the summer is expected to completely disappear by the end of the 21st century.
4. The sea level has risen 22 cm since 1880 due to the expansion of the water as it becomes warmer. Additionally, the melting of glaciers in Greenland and Antarctica has already contributed almost as much to this phenomenon. If the emission of CO2 and methane continues as today, by the end of the 21st century the sea level will be very likely 100 cm higher than it is today, threatening many urbanized coastal areas.
5. According to the World Meteorological Organization, the number of natural disasters has multiplied by five since 1970 adding up to more than eleven thousand during this period. Around 90% of human losses from these disasters have occurred in developing countries, with droughts being the major cause. Although the number of people who die in the world due to climatic events has fallen from 60 thousand to 20 thousand per year, the economic costs have increased from 20 billion dollars a year to 140 billion, taking current prices.
Forecasts on the effects of climate change are clearly pessimistic, but because they are based on extremely complex mathematical models they also contain a high degree of uncertainty. For example, at the end of the 20th century it was said very firmly that due to climate change hurricanes would become more frequent and powerful, but this has not been the case in the last 25 years.
In the same way, since the 70s, environmental social movements and many scientists have declared that the end of humanity is just around the corner due to overpopulation and pollution. The truth is that increases in agricultural productivity have substantially reduced hunger in the world and the presence of toxic substances in ecosystems has decreased in most countries thanks to technological improvements.
Since the 00s, most developed countries have progressively reduced their total CO2 emissions, including the United States. However, during climate negotiations to reduce the use of fossil fuels, developing countries argue that rich countries are responsible for the overwhelming majority of CO2 and methane that has been put into the atmosphere since the Industrial Revolution, thus requiring financial aid as compensation.
During the last of these negotiations, held during the COP26 (Conference of the Parties) in Glasgow, the countries agreed to:
1. Gradually reduce the use of fossil fuels by 2030. Specifically, a commitment was signed to close coal plants and stop selling internal combustion cars by 2040. The initial document aimed towards a 'total reduction of carbon use' but India and China opposed and vetoed that resolution.
2. Plant many trees and protect forests in their respective territories.
3. An increase in financial aid from developed countries by giving more than 100 billion dollars annually to developing countries.
4. A standardized mechanism to measure the emissions of each country.
5. To report on the progress countries have made regarding climate actions towards the COP27, next year in Sharm el-Sheik, Egypt.
These commitments will not make it possible to achieve the Paris Agreement objective regarding having an increase of less than 1.5 °C by 2100 compared to the beginning of the Industrial Revolution temperature. Forecasts instead show that world temperature will increase 2.7 °C by 2100, and the Glasgow measures will reduce this increase by only 0.3 °C. To reach the goal of 1.5°C, which is considered the limit to avoid drastic changes on the climate, the net emission of greenhouse gases must be zero by 2030.
Currently, 25 billion tons of CO2 are expelled each year and the commitments are only going to reduce 5 billion of these tons, so there is still a huge surplus of gases within this climate action plan. The smaller island countries were the most disappointed by the results of COP26. Some, like the Maldives, argue that they are exposed to 'a climate extinction' if the increase in temperature is not limited to 1.5 °C.
Moreover, poor countries were unable to get a signed damage-recovery clause by which poor countries affected by a natural disaster could sue rich countries for causing this damage and thus obtain additional financial compensation. The only way today to achieve zero greenhouse gas emissions by 2030 without radically transforming the economy and society is by betting on investing massively in CO2 absorption technologies that keep it underground. This method is very recent and costs an average of $500 per ton of CO2, still being relatively expensive.
However, the history of the case of solar panels, that received huge government subsidies and the massive scale production that followed, allowed to drastically reduce their unit price after 20 years. This gives a hopeful perspective regarding this type of technology as a solution to a possible climate crisis.