If the world gets two degrees Celsius warmer, we are doomed. To prevent this, the UN signed the Paris Agreement, an international treaty under which the signatories will try to keep the global average temperature "2 ° C below pre-industrial levels." The pre-industrial level was when factories had not yet begun to poison the clear sky with their gases.
Over the past 20 years, this two-degree threshold has been repeatedly mentioned in political speeches and agreements adopted by the Council of the European Union, the G8 (G8, now G7) and others.
Why is 2 degrees so important?
It all began in 1975, when economist William Nordhaus saw a warming planet as a threat to the global economy. He asked his colleagues at the International Institute for Applied Systems Analysis: Can we control carbon dioxide? Nordhaus came to the conclusion that a 2 ° C increase in global average temperature (caused by man-made emissions of carbon dioxide into the air) will change our climate in ways that have not happened before for several hundred thousand years.
Where did the economist get these 2 degrees from? Nordhaus turned to science. Since he knew that carbon dioxide warms the planet, Nordhaus calculated what would happen if the concentration of carbon dioxide in the atmosphere doubled - resulting in a global increase of 2 degrees. He also predicted that at our current pace, we are moving into a "danger zone" beyond 2 degrees and will be there in 2030.
Over the next 20 years, scientists warned of the dangers of rising temperatures associated with greenhouse gas emissions. In 1992, the United Nations Framework Convention on Climate Change was created to end dangerous human interference with the climate without limiting emissions or increasing global temperatures. It took another four years for 2 degrees to take root in the public consciousness and reach the ministers of ecology of the European Union. Ultimately, the UN ratified the two-degree limit in the Paris Agreement … in 2016. More than forty years after Nordhaus first spoke of him.
It would seem, what is two degrees? We experience temperature fluctuations every day and more. However, climate change and global warming are long-term trends.
During the 20th century, the average global temperature was about 14 degrees, plus or minus a few tenths of a degree. The globe has warmed by almost a full degree since 1880, but more than two-thirds of this increase has occurred since 1975, when Nordhaus wrote his article. Every year in the 21st century was included in the twenty warmest years.
Promotional video:
The last time the Earth was as warm as it is now was 11,000 years ago. The oceans cover 70% of the planet's surface, and it takes a lot of energy to heat this amount of water, not to mention air and land. Therefore, an increase in global average temperature of 2 degrees means that in some places the temperature rise exceeded these 2 degrees.
We already feel the consequences of our actions - so the weather seems stranger than it used to be. Hurricane Harvey hit Houston in 2017, and its unprecedented downpour was 10 times more likely to be due to human interference with the natural course of the climate. Drought and heat waves also intensified, in some regions the amount of precipitation decreased and forest fires became active.
If we get 2 degrees warmer, the world will be much drier, which will affect the economy, agriculture, infrastructure and weather conditions. Rising temperatures can harm ecosystems and species that cannot adapt, including coral reefs and arctic inhabitants. Low coastal areas and small islands around the world are at risk of disappearing as sea levels rise, associated with the melting of Arctic ice caps and the Greenland ice sheet. 2 degrees Celsius can determine the existence of entire nations.
The Intergovernmental Panel on Climate Change, an organization that advises governments on the causes and effects of climate change, is now examining what the world will be like if the average temperature rises by three, four degrees, or even higher. This could lead to the extinction of entire species and huge risks to global and regional food security. People will not be able to live and work in some areas of the world.
Will large countries, especially China and India, be able to limit carbon dioxide emissions to keep our planet below 2 degrees? Hardly. Research shows that we have a 95 percent chance of being 2 degrees warmer by 2100, and the negative effects of climate change will be very dire. We have the ability to reduce our emissions and contain the worst possible warming. But time is running out.
Ilya Khel