The climate changes we have observed in recent decades are largely the result of an imbalance in the natural composition of the Earth’s atmosphere. The greenhouse gases that contribute to so many problems today have been present in the air for a very long time. They are formed by natural processes – especially methane (CH4) and carbon dioxide (CO2) – and are needed to sustain life on Earth (eg. CO2 is involved in photosynthesis, so it is necessary for plants to function). Both CH4 and CO2 affect the average air temperature on Earth.
Greenhouse gases trap some of the energy supplied by the sun near Earth. A decrease in their concentration would cause an increase in the emission of heat from the Earth into space, resulting in a decrease in air temperature. An increase in their concentration has the opposite effect: heat is retained in the atmosphere, so the airtemperature rises. CO2, emitted into the atmosphere as a result of human activity, is primarily responsible for disrupting the natural balance. The sharp increase in the magnitude of this phenomenon in the last two centuries is mainly due to the development of industries using energy from the combustion of non-renewable fuels and massive deforestation.
Among the most serious, most acute effects of rising CO2 concentrations are an increase in average air temperature, a rise in sea and ocean temperatures, the melting of glaciers and in the mean sea levels.
United Nations experts alert: “Greenhouse gas concentrations are at their highest levels in 2 million years and emissions continue to rise.
As a result, the Earth is now about 1.1 Celsius degrees warmer than it was in the late 1800s. The last decade (2011–2020) was the warmest on record.
Many people think climate change primarily means warmer temperatures. But higher temperature is only the beginning of the story. Because the Earth consists in the system where everything is connected, changes in one area may influence changes in all others.
The consequences of climate change now include, among others, intense droughts, water scarcity, severe fires, rising sea levels, flooding, melting polar ice, catastrophic storms and declining biodiversity.
(...) In a series of United Nations reports, thousands of scientists and government reviewers agreed that limiting global temperature rise to no more than 1.5 Celsius degrees would help us avoid the worst climate impacts and maintain a livable climate.
Yet based on current national climate plans, global warming is projected to reach around 3.2 Celsius degrees by the end of the century”.
The melting of the ice sheet, icebergs and glaciers feeds the seas and oceans with large amounts of water, causing the average sea level to rise.
Rising temperatures have further secondary effects, including a higher incidence of dangerous weather events such as tornadoes and violent storms. Desertification and land degradation are intensifying, and the threat of famine is increasing as a result.
IPCC Special Report on Climate Change and Land autors say: “Land degradation adversely affects people’s livelihoods and occurs over a quarter of the Earth’s ice-free land area. The majority of the 1.3 to 3.2 billion affected people are living in poverty in the developing countries”.
