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Major floods in China, province heralds highest alarm

Southern China’s Jiangxi Province has issued the highest flood alarm. It is warned that dams can fail and that extreme flooding is possible on several rivers. China has been plagued by floods for weeks, caused by heavy rain.

In Jinagxi, some 5 million people have now been affected by the floods. According to state media, a total of 34 million Chinese have been affected by the storm. At least 121 people are said to have died or gone missing. The storm is moving further east along the Yangtze River.

The Hong Kong newspaper The South China Morning Post made this report about the disaster:

Poyang Lake, the largest freshwater lake in China, is located in Jiangxi Province. According to the authorities, the water level could exceed the record in 1998. In that year, the worst floods in decades were in China: 4,000 people died and tens of millions were affected by the disaster.

Wuhan, the city where the coronavirus first spread, also suffers from severe weather. Early this week, the city raised the flood alert to the next-highest level.

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Earth’s atmosphere “rings” like a bell

At the beginning of the 19th century, the physicist Pierre-Simon Laplace hypothesized that the atmosphere is traversed by pressure waves at the origin of a global phenomenon of atmospheric resonance. For many years, geophysicists will deepen and clarify this idea, in particular by identifying the frequencies expected for these waves. However, it was only recently that a team of researchers was finally able to identify and confirm the presence of these waves, causing the atmosphere to vibrate like a bell. 

A ringing bell vibrates simultaneously with a deep fundamental tone and numerous high harmonics, producing a characteristic musical sound. A recent study, published in the Journal of the Atmospheric Sciences by geophysicists at the University of Kyoto and the University of Hawaii at Mānoa, shows that the entire atmosphere of the Earth vibrates in an analogous manner, confirming theories developed by physicists over the past two centuries.

In the case of the atmosphere, “music” emerges in the form of large-scale atmospheric pressure waves covering the globe and travelling around the equator, some moving east to west and others moving west to east. Each of these waves is a resonant vibration of the global atmosphere.

The basic understanding of these atmospheric resonances began with ideas expressed at the beginning of the 19th century by one of the greatest scientists in history, the French physicist and mathematician Pierre-Simon Laplace. Research by physicists over the next two centuries refined the theory and led to detailed predictions of the frequencies of the waves that should be present in the atmosphere. However, the actual detection of such waves lagged behind the theory.

Pressure waves at the origin of a real atmospheric resonance

The new study by Takatoshi Sakazaki, professor at the Graduate School of Science at Kyoto University, and Kevin Hamilton, professor at the Department of Atmospheric Sciences and at the International Pacific Research Center at the University of Hawaii, presents a detailed analysis of the atmospheric pressure observed on the globe every hour for 38 years. The results clearly revealed the presence of dozens of previously predicted wave modes.

The study focused in particular on the waves with periods between 2 hours and 33 hours which move horizontally through the atmosphere, moving around the globe at high speed (exceeding 310 km / h). This establishes a characteristic “checkerboard” pattern of high and low pressure, associated with these waves as they propagate.

“ Our identification of so many modes in real data shows that the atmosphere sounds good as a bell. This finally solves an old and classic problem in atmospheric science, but it also opens up a new avenue of research to understand both the processes that excite waves and the processes that act to dampen waves, “Hamilton concludes.

Sources:  JAS
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World temperature will remain at least 1 degree warmer for the next five years

Until 2025, the average temperature on Earth will remain at least 1 degree warmer than the average in the second half of the 19th century. Moreover, there is a one in five chance that the temperature in one of those years will be 1.5 degrees above the average of that pre-industrial era for the first time. These are the main conclusions from the annual climate forecasts of the World Meteorological Organization (WMO).

In the Paris climate agreement, almost the entire world agreed in 2015 to keep the temperature rise below 2 degrees and to strive for a maximum of 1.5 degrees of warming. “This study demonstrates – with a high degree of scientific quality – the enormous challenges of meeting the Paris climate goals,” said WMO Secretary-General Petteri Taalas.

The average global temperature is already 1.1 degrees higher than the average in the period 1850-1900, the WMO reported in January. It also turned out that the past five years had been the hottest years on average since the measurements began. The WMO now says that the world temperature in the next five years is very likely to be between 0.91 and 1.59 degrees above that of the pre-industrial era.

‘Corona crisis not an alternative to climate policy.’

The effect of the corona pandemic has not been included in the calculations. Taalas warns governments that the economic crisis and reduced industrial activity cannot replace a sustainable climate policy. “They should seize this opportunity to make climate policy part of the recovery programs. Failure to address climate change has threatened the wellbeing of people, ecosystems, and economies for centuries.”

The research was conducted under the direction of the Met Office, the British counterpart of the KNMI. According to the WMO, the British took advantage of the expertise of leading climate scientists and their best computer models.