The tropical belt expanded faster than expected

The tropical belt is expanding the area of ​​the two poles of the globe, according to a study by American scientists published on the National Geographic Science website on December 2.

Scientists have discovered that in the last 25 years, the area with a tropical climate has expanded a total of 277km towards the two poles, that is, the earth now has an additional 22 million km ² of a tropical climate .

The Independent newspaper said the study was a joint work of Dr. Dian Seidel of the Washington National Oceanic and Atmospheric Administration (USA) with several colleagues.

The research results of Dr. Dian Seidel and colleagues may be considered " shocking", because it shows that the tropical belt expands much and is faster than forecast. Global climate computer programs of the United Nations Climate Change Commission predict that by the end of the 21st century, the tropical region will expand to a maximum of 2 degrees on the parallel to the poles. The results of Dr. Dian Seidel and colleagues show that this belt has now expanded by 2.5 degrees.

According to Wikipedia's encyclopedia, the tropical region (also known as the equator) is a geographic area on Earth that lies within the boundary of two lines: the lower band in the northern hemisphere and east Tropic of Cancer in the southern hemisphere, including the equator.

Meteorologists have a more complex definition of the boundary of the tropics, based on five different criteria groups, mainly describing air currents and currents around the equator.Just above the equator, the air is very hot, carrying moisture is an important factor in tropical storms.The farther away from the equator, the lower the amount of air, which makes the equatorial area drier.Scientists found that the border region of the tropics is expanding toward the two poles.

According to the researchers, this expansion leads to the movement of tropical climatic characteristics towards the poles, which can lead to changes in the characteristics of rainfall, affecting natural ecosystems. , agriculture and water resources.

The affected area is quite large, including a large area of ​​the Mediterranean, southwest of the United States, northern Mexico, southern Australia, southern Africa and parts of South America. " The increase in tropical belt area may make more areas affected by tropical storms. The progress and characteristics of these storms also become more unpredictable, " the report said.

In addition, the expanding tropical belt will contribute to exacerbate the global warming, as it increases the speed of water pumping into the high gas layer.

Australia is one of the countries most at risk of being affected by tropical belt expansion, due to winds blowing from the west which bring the necessary rainfall to the country's arid coastline. pushed to the south, rainwater poured into the vast ocean instead of on land.

Professor Barry Brook of the University of Adelaide (Australia) affirmed that the tropical belt expansion will inevitably lead to the expansion of tropical pathogens and pathogenic insects."The global sign of the rapid expansion of the tropical belt reinforces the fact that climate change is happening faster than forecast," he stressed.

The study was published at the time of the climate change conference opening in Bali, Indonesia. About 10,000 delegates, scientists and journalists from nearly 190 countries opened the largest international conference ever organized by the United Nations on climate change, with the aim of building an international treaty. New in 2009 to deal with global warming, or economic and environmental disasters due to rising temperatures.

The illustration shows that the area with a tropical climate (blue) has expanded towards the poles of the earth.(Photo: TTO)

Australia ratified the Kyoto protocol

Drought cracks soil in New South Wales (Australia).Increased drought in recent years in Australia may be the result of tropical belt expansion

Reuters source said the new Australian Prime Minister Kevin Rudd has ratified the Kyoto protocol shortly after being sworn in on December 3.

The move of the 50-year-old prime minister has turned America into the only developed country that has not yet ratified the protocol to limit carbon emissions.

"This is the first official act of a new Australian Government, demonstrating the government's commitment to addressing climate change," Rudd said.

THANH TRUC