It is now the cold winter in the northern hemisphere, but the summer in the southern hemisphere, and many places are experiencing the baptism of high temperatures.
According to media reports, Argentina, Australia, Uruguay and other countries have experienced extreme high temperature weather, Australia's western coastal town of Angslow, even appeared a high temperature of 50.7 ° C, leveling the local 60 years to create the highest temperature record in the southern hemisphere, higher than the same period in previous years the temperature of more than 10 ° C, very abnormal, the World Meteorological Organization is currently verifying this record.
Extreme high temperatures have brought serious impacts to the local area, increasing the consumption of water, electricity and other resources, and easily causing infrastructure to be destroyed at high temperatures, such as: road deformation and collapse, vehicle engine overheating, etc. Extreme heat has led to local vegetation being very susceptible to spontaneous combustion in heat waves, triggering forest fires, and many parts of Argentina have been hit by wildfires.
The situation in Australia is not optimistic, there have been a large-scale heat wave in many places, a local citizen said: he originally planned to go to the shade to rest, the result is that the temperature in the shade of the place is too high, must go to a place with air conditioning, otherwise it will be heat stroke.
The concern is that Australian forests are more susceptible to wildfires at high temperatures, and large-scale wildfires could lead to more serious disasters.
Extreme heat and wildfires
According to the Global Forest Watch Fire Monitoring and Early Warning System, more than 70% of fires occur mainly in forest areas composed of different eucalyptus trees.
This is mainly because eucalyptus leaves are rich in oil, which constantly volatilizes into the air, leaving the local forest shrouded in grease smoke. Among them, the higher the local temperature, the faster the oil volatilization rate, and the higher the oil content in the air, the easier it is to spontaneously combust, so in the high temperature heat wave, eucalyptus forest is prone to wildfires. In the event of a wildfire, eucalyptus's oil-rich leaves will help the wildfire spread and spread over a wider area.
Eucalyptus trees will become the "assist" of the mountain fire, mainly because eucalyptus trees need fire to grab the land, eucalyptus tree core is hidden deep inside, the mountain fire can only burn off its leaves and skin, can not hurt the heart, so after the wildfire eucalyptus trees can quickly recover, at this time they will preempt other vegetation restoration, they will seize the upper space of the forest, resulting in vegetation that has not yet recovered is difficult to photosynthesize, it is difficult to grow, so it is gradually expelled from the forest.
Forest fires will burn the fruit of the plant and make it inactive, but the fruit of the eucalyptus tree has a thick shell, which is difficult to germinate under normal circumstances, and can only take root and sprout better after the burning of the forest fire.
It is precisely because of this that eucalyptus trees can survive forest fires very well, which also leads to more and more local eucalyptus trees if there are frequent wildfires in one place.
This is the case in Australian forests, where the vast majority of vegetation is eucalyptus, but because eucalyptus is more likely to burn, it is more likely to have forest fires than other places. Therefore, this time Australia suffered from high temperature heat waves, there are people who are worried that there will be wildfires in the local area again, but in fact, several bushfire warnings in Australia have been issued. Once a local forest fire occurs, the heat wave will exacerbate the severity of the wildfire and even have a catastrophic impact on the local area.
global warming
Although it is not yet known what is responsible for the abnormal heat in the southern hemisphere, there is no doubt that this high temperature heat wave is also related to global warming.
According to the World Meteorological Organization, temperatures are now 1.2°C higher than they were before industrialization. According to this trend, by 2100 global temperatures will be 3-5°C higher than pre-industrial levels.
The temperature of 1-2 °C may not seem high for many people, but it should be known that global warming is not uniform, and the difference of 1-2 °C is enough to cause global disasters.
For example, the eruption of Mount Tambora in 1815 caused the average global temperature to drop by 0.4 to 0.7 degrees Celsius in the next 1-2 years, resulting in the "summerless year" in the northern hemisphere in 1816, and it is estimated that 200,000 people died from this extreme weather in Europe alone.
The impact of global warming is not only the rise in global temperatures, but also the frequency of extreme weather, such as: in the past 2021, the earth suffered natural disasters such as thermal domes, extreme heat, and extreme rainstorms. And if global warming continues, it will cause these extreme events to become more extreme and even more common.
On the other hand, global warming will also lead to the melting of polar permafrost and the melting of glaciers, causing sea levels to rise and some low-lying cities to be submerged.
The melting of glaciers will cause more sun to enter the earth's surface, and the earth will heat up faster. When the Earth's temperature reaches a critical point, there is only a limit to what humans can do.
Fortunately, many countries and regions around the world have realized the seriousness of the problem and have begun to actively respond to climate change, and the mainland has promised to peak carbon dioxide emissions by 2030 and strive to achieve carbon neutrality by 2060.