Humans are in danger of extinction

Scientists have recently warned that humans may face an unexplored risk of extinction.

Accordingly, in an analysis of human extinction, climate scientists have warned that it is an unexplored danger. The new analysis was published in the journal Proceedings of the National Academy of Sciences and has also been reviewed by dozens of scientists.

Experts call the disaster "the end of the climate". Although the probability is small, due to the uncertainty of future emissions and the climate system, the prospect of humans facing a cataclysm cannot be ruled out.

Faced with a future of accelerating climate change, scientists warn, there are reasons to doubt that global warming could lead to apocalyptic catastrophe.

Therefore, the international group of experts believes that the world needs to start preparing for the possibility of a climate war. Conducting an analysis of the mechanisms underlying these extreme consequences can help spur action and improve resilience, while informing policy, experts say.

Climate change is one of the causes of many fires.

In this new analysis, the scientists also propose a research agenda, including four key issues they call the "four horsemen" of the end of climate, including: hunger, weather hardship, war, disease.

In fact, scientists have called on the Intergovernmental Panel on Climate Change to issue a special report on this issue.

Dr Luke Kemp at the University of Cambridge's Center for Existential Risk Research, who led the analysis, said: "There are many reasons to believe that climate change could turn out to be catastrophic, even if the temperature at which the Earth warms is within a small range".

This expert emphasized, fact proves that climate change has played a certain role in every mass extinction event. This is also considered one of the factors that led to the collapse of empires and shaped history.

The paths to disaster are not limited to the direct effects of high temperatures, such as extreme weather events. In addition, chain reactions such as financial crises, conflicts and new disease outbreaks can cause other disasters.

However, the analysis by climate scientists also shows that the consequences of global warming exceeding 3 degrees Celsius are still poorly studied and there are few quantitative estimates of the total impact. .

A thorough risk assessment will look at how risks spread, interact with each other and amplify, the scientists say. However, this has not been done yet. For example, an assessment of a tornado that destroys electrical infrastructure could leave people vulnerable to the deadly heatwave that follows.

However, according to the scientists, there is a special issue that needs attention: the tipping point in the climate system. So, what is the cut-off point?

According to experts, the tipping point is the time when ecology, climate . are changed to an irreversible extent, even if humans do not destroy the environment or increase carbon emissions. For example, if the tipping point, a huge carbon sink of the Earth like the Amazon rainforest, is crossed, it could also be subject to drought and major fires.

Humans face the risk of extinction in the future because of climate change.

The tipping points can lead to a domino effect, the researchers warn, while also triggering others. In fact, some are still not well studied, such as the sudden disappearance of stratospheric clouds that can cause the Earth's temperature to warm by 8 degrees Celsius.

In addition, the researchers warn that climate change could exacerbate vulnerabilities such as water shortages, crop failure and poverty; or trigger other catastrophic risks, such as pandemics, international wars.

Experts' analysis also shows that one day, superpowers may clash over geoengineering plans (a new term for ideas about cooling the Earth by direct impact techniques). to the planet to deal with climate change), or the right to carbon emissions.

Thus, if the current "fragility" situation does not significantly improve in the coming decades, a belt of instability with the potential for severe fragmentation could occur.

The scientists emphasize that climate change has played an important role in the collapse or transformation of many previous societies, and especially in the five mass extinction events of Earth's history.

Notably, the new modeling in this analysis suggests that extreme heat (defined as average annual temperatures above 29 degrees Celsius) could affect 2 billion people by 2070, if carbon emissions The problem continues to grow as it is today.

"Such high temperatures are affecting about 30 million people in the Sahara and the Gulf Coast of Mexico," said researcher Chi Xu at Nanjing University, China.

Forecasting the "scenario" of the 6th mass extinction on Earth

Recently, there is a study by climate scientist Kunio Kaiho from Tohoku University, Japan, published in the journal Biosciences. This study has predicted the 6th mass extinction event. According to this expert, the 6th mass extinction on Earth will not be as catastrophic as the 5 times in the past.

When conducting an analysis of the relationship between the stability of the Earth's average surface temperature and biodiversity, Mr. Kunio Kaiho found that extinction levels increase as temperatures change. .

Experts predict the 6th mass extinction on Earth.

In fact, the largest mass extinctions of the global warming occurred when the temperature dropped by about 7 degrees Celsius. But according to this expert, during the period of global warming, the extinctions. The largest mass strain occurred as temperatures on the planet warmed by about 9 degrees Celsius.

This number is actually significantly higher than previous predictions. This shows that if the temperature increases by 5.2 degrees Celsius, it will cause mass extinctions like in marine ecosystems with the same magnitude as the previous 5 extinctions.

According to a United Nations report, global warming is forecast to increase the Earth's surface temperature by up to 4.4 degrees Celsius by the end of this century.

However, according to Kunio Kaiho, using only surface temperatures, it is difficult to predict the magnitude of future human-caused extinctions. By the fact that the cause of the anthropogenic extinction is different from the cause of the mass extinction in geological time.

As a result of climate change, many species of animals on land and in the sea become extinct, although researchers do not anticipate the extent of damage in the past.

Today's global warming is happening over a much shorter period of time due to anthropogenic emissions of more greenhouse gases. This could lead to more species becoming extinct in the Earth's 6th mass extinction. The reason is not because the level of warming is too great, but because the changes are happening too quickly for many species to adapt.

Humans were close to extinction?

Humans have experienced periods of severe population decline, even near extinction.

Humans (Homo sapiens) have existed for about 300,000 years. During this long time, humans have increased significantly in both territory and numbers. However, the reality is that life on Earth is not always easy. According to experts, there are times when humans have to face the danger of extinction. Why?

Humans have experienced massive population declines.

Specifically, one of the above events occurred about 190,000 years before the Earth entered the ice age. During this period, the Earth mostly became cold and dry. This leads to the formation of glaciers and ice deserts.

This glacial state lasted about 60,000 years. In particular, as habitable areas shrink, so does the human population. According to estimates by some geneticists, the number of fertile people has decreased from about 10,000 to just 600.

Many of these people live on the south coast of Africa. It is rich in carbohydrate-rich plants, protein-rich shellfish and warm ocean currents. Because of that, this group of people seems to have thrived.

In particular, one woman, a member of this group, is what scientists call the human "mitochondrial Eve". This woman contains the mitochondrial DNA origin of all humans today and became the common ancestor of all mankind.

Since then, however, genetic mutations and variations have piled up. It is for this reason that scientists have created seed room diagrams.

Specifically, during the study, experts found that, compared to other animals, humans turned out to be not much different in terms of genes. Instead, they believe, this is the result of another significant decline in population size.

This decline is estimated to have occurred about 70,000 years ago. At that time only about 2,000 people survived.

The actual cause of the human population decline is still controversial.

According to old theories, the cause is Mount Toba in Indonesia, erupting. This event produced 2,800 square kilometers of ash and lava, while blocking the Sun and triggering an ice age. But later studies showed that people turned out not to be affected by this event too much.

Whatever the cause, the human population has overcome it. In addition, the human population reached the 1 million mark around 12,000 years ago. According to experts, the Earth's population will reach 8 billion people by 2022.