The end of the climate as we know it. A few steps are enough...

The climate on planet Earth has changed many times. Warmer than it is now, much warmer, it has been for most of its history. Cooling and glaciation turned out to be relatively short-term episodes. So what makes us treat the current temperature spike as something special? The answer is: because we call it, we, homo sapiens, with our presence and activity.

The climate has changed throughout history. Mainly due to its own internal dynamics and the influence of external factors such as volcanic eruptions or changes in sunlight.

Scientific evidence shows that climate change is perfectly normal and has been happening for millions of years. For example, billions of years ago, during the formative years of life, the average temperature on our planet was much higher than today - nothing special when it was 60-70 ° C (remember that the air had a different composition then). For most of the Earth's history, its surface was completely ice-free - even at the poles. The eras when it appeared, compared with several billion years of the existence of our planet, can even be considered quite short. There were also times when ice covered large parts of the globe - these are what we call periods. ice ages. They came many times, and the last cooling comes from the beginning of the Quaternary period (about 2 million years). Intertwined ice ages occurred within its boundaries. periods of warming. This is the warming we have today, and the last ice age ended 10 years. many years ago.

Two thousand years of the average temperature of the Earth's surface according to different reconstructions

Industrial revolution = climate revolution

However, over the past two centuries, climate change has progressed much faster than ever before. Since the beginning of the 0,75th century, the temperature of the surface of the globe has increased by about 1,5°C, and by the middle of this century it may increase by another 2-XNUMX°C.

Prediction of global warming using various models

The news is that now, for the first time in history, the climate is changing. influenced by human activities. This has been going on ever since the industrial revolution began in the mid-1800s. Until about the year 280, the concentration of carbon dioxide in the atmosphere remained practically unchanged and amounted to 1750 parts per million. The massive use of fossil fuels such as coal, oil and gas has led to an increase in greenhouse gas emissions into the atmosphere. For example, the concentration of carbon dioxide in the atmosphere has increased by 31% since 151 (methane concentration by as much as 50%!). Since the end of the XNUMXs (because systematic and very careful monitoring of the CO content in the atmosphere₂) the concentration of this gas in the atmosphere jumped from 315 parts per million (ppm of air) to 398 parts per million in 2013. With the increase in fossil fuel burning, the increase in CO concentration is accelerating.₂ in the air. It is currently increasing by two parts per million every year. If this figure remains unchanged, by 2040 we will reach 450 ppm.

However, these phenomena did not provoke Greenhouse effect, because this name hides a completely natural process, which consists in the retention by greenhouse gases present in the atmosphere of part of the energy that previously reached the Earth in the form of solar radiation. However, the more greenhouse gases in the atmosphere, the more of this energy (heat radiated by the Earth) it can hold. The result is a global rise in temperature, that is, popular global warming.

Carbon dioxide emissions by "civilization" are still small compared to emissions from natural sources, oceans or plants. People emit only 5% of this gas into the atmosphere. 10 billion tons compared to 90 billion tons from the oceans, 60 billion tons from soil and the same amount from plants is not much. However, by extracting and burning fossil fuels, we are rapidly introducing a carbon cycle that nature removes from it over tens to hundreds of millions of years. The observed annual increase in the concentration of carbon dioxide in the atmosphere by 2 ppm represents an increase in the mass of atmospheric carbon by 4,25 billion tons. So it's not that we're emitting more than nature, but that we're upsetting the balance of nature and throwing large excesses of CO into the atmosphere each year.₂.

Vegetation enjoys this high concentration of atmospheric carbon dioxide so far because photosynthesis has something to eat. However, shifting climate zones, water restrictions and deforestation mean that there will be no “one” to absorb more carbon dioxide. An increase in temperature will also accelerate the processes of decay and the release of carbon through soils, leading to melting permafrost and release of trapped organic materials.

The warmer, the poorer

With warming, there are more and more weather anomalies. If changes are not stopped, scientists predict that extreme weather events — extreme heat waves, heat waves, record rainfall, as well as droughts, floods and avalanches — will become more frequent.

The extreme manifestations of the ongoing changes have a strong impact on the life of humans, animals and plants. They also affect human health. Due to climate warming, i.e. the spectrum of tropical diseases is expandingsuch as malaria and dengue fever. The effects of the changes are also being felt in the economy. According to the International Panel on Climate Change (IPCC), a 2,5 degree rise in temperature will make it global. decline in GDP (Gross domestic product) by 1,5-2%.

Already when the average temperature rises by only a fraction of a degree Celsius, we are seeing a number of unprecedented phenomena: record heat, melting glaciers, increasing hurricanes, the destruction of the Arctic ice cap and Antarctic ice, rising sea levels, melting permafrost, storms. hurricanes, desertification, droughts, fires and floods. According to experts, the average temperature of the Earth by the end of the century rise by 3-4°С, and the lands - within 4-7 ° C and this will not be the end of the process at all. About a decade ago, scientists predicted that by the end of the XNUMXth century climate zones will shift on 200-400 km. Meanwhile, this has already happened in the last twenty years, that is, decades earlier.

 Ice loss in the Arctic - 1984 vs. 2012 comparison

Climate change also means changes in pressure systems and wind directions. The rainy seasons will change and the rainfall areas will change. The result will be shifting deserts. Among others, southern Europe and the USA, South Africa, the Amazon basin and Australia. According to a 2007 IPCC report, between 2080 and 1,1 billion people will remain without access to water in 3,2. At the same time, more than 600 million people will go hungry.

Water above

Alaska, New Zealand, the Himalayas, the Andes, the Alps - glaciers are melting everywhere. Due to these processes in the Himalayas, China will lose two-thirds of the mass of its glaciers by the middle of the century. In Switzerland, some banks are no longer willing to lend to ski resorts located below 1500 m above sea level. In the Andes, the disappearance of rivers flowing from glaciers leads not only to problems with the provision of water to agriculture and the townspeople, but also to power outages. In Montana, in Glacier National Park, there were 1850 glaciers in 150, today only 27 remain. It is predicted that by 2030 there will be none left.

If the Greenland ice melts, sea levels will rise by 7m and the entire Antarctic ice sheet will rise by as much as 70m. Global sea levels are predicted to rise by 1-1,5m by the end of this century, and later, gradually rise another as much as XNUMX m. for several tens of meters. Meanwhile, hundreds of millions of people live in coastal areas.

Village on the island of Choiseul

Villagers on Choiseul Island In the archipelago of the Solomon Islands, they have already had to leave their homes due to the risk of flooding caused by rising water levels in the Pacific Ocean. The researchers warned them that due to the risk of severe storms, tsunamis and seismic movements, their homes could disappear from the face of the Earth at any moment. For a similar reason, there is a process of resettlement of the inhabitants of the Han Island in Papua New Guinea, and the population of the Pacific archipelago of Kiribati will soon be the same.

Some argue that warming could also bring benefits - in the form of agricultural development of the now almost uninhabited regions of the northern Canadian and Siberian taiga. However, the prevailing opinion is that on a global scale this will bring more losses than benefits. The rise of the water level would cause a huge scale of migration to higher regions, water would flood industries and cities - the price of such changes could be fatal to the world economy and civilization as a whole.