Computing collaboration reveals global ripple effect of shifting monsoons

Phys.org  June 29, 2020 An international team of researchers (USA – Oak Ridge National Laboratory, UCLA, Mexico, Brazil, Italy, Hong Kong, Nigeria, Senegal, Rwanda, Pakistan) used an ensemble of regional climate model (RCM) projections over seven regional CORDEX domains to provide an elaborate set of projections to date that illustrates possible futures for major monsoon regions. Each simulation covers the period from 1970 through 2100. They found that the weakening of latent heat driven atmospheric warming during the pre-monsoon period delays the overturning of atmospheric subsidence in the monsoon regions, which defers their transitioning into deep convective states. This causes […]

Warnings Issued as Unusually Thick Cloud of Saharan Dust Approaches The US

Science Alert  June 25, 2020 The dust cloud swept across the Atlantic from Africa over the past week, covering the Caribbean island of Puerto Rico since Sunday and hitting south Florida on Wednesday. Powered by strong winds, dust from the Sahara travels across the Atlantic Ocean from West Africa during the boreal spring. But the density of the current dust cloud over Cuba is well above normal levels. The dust clouds are loaded with minerals such as iron, calcium, phosphorous, silicon and mercury, and viruses, bacteria, fungi, pathogenic mites, staphylococci and organic pollutants…read more.

A Devastating US ‘Dust Bowl’ Is Twice as Likely Now Than During The Great Depression

Science Alert  May 19, 2020 During 1930s Dust Bowl drought across North America’s Great Plains caused widespread crop failures, large dust storms and considerable out-migration. This coincided with the central United States experiencing its hottest summers of the twentieth century in 1934 and 1936, with over 40 heatwave days and maximum temperatures surpassing 44 °C at some locations. According to an international team of researchers (Australia, UK, Sweden) heatwave activity in similarly rare events would be much larger under today’s atmospheric green house gas forcing the return period of a 1-in-100-year heatwave summer (as observed in 1936) would be reduced to […]

Long-term data show hurricanes are getting stronger

Science Daily  May 18, 2020 Previous work by a team of researchers at NOAA identified trends in hurricane intensification across a 28-year data set. To increase confidence in the results, the researchers extended the study to include global hurricane data from 1979-2017. Using analytical techniques that rely on infrared temperature measurements from geostationary satellites to estimate hurricane intensity, they were able to create a more uniform data set to identify trends. They demonstrated that hurricanes are moving more slowly across land due to changes in Earth’s climate. This has resulted in greater flood risks as storms hover over cities and […]

A billion years missing from geologic record: Where it may have gone

Science Daily  May 7, 2020 The Great Unconformity, as it is known, accounts for more than one billion years of missing rock in certain places. Scientists have developed several hypotheses to explain how, and when, this staggering amount of material may have been eroded. Using the ratio of helium to thorium and uranium in certain minerals as a paleo-thermometer a team of researchers in the US (University of Colorado, UC Santa Barbara) tracked how rock moved in the crust as it was buried and eroded through the ages. They extracted grains of a particularly resilient mineral, zircon, from the stone […]

Potentially fatal combinations of humidity and heat are emerging across the globe

Science Daily  May 8, 2020 Humans’ ability to efficiently shed heat has enabled us to range over every continent, but a wet-bulb temperature (TW) of 35°C marks our upper physiological limit, and much lower values have serious health and productivity impacts. An international team of researchers (USA – Caltech. Columbia University, UK) found that a comprehensive evaluation of weather station data shows that some coastal subtropical locations have already reported a TW of 35°C and that extreme humid heat overall has more than doubled in frequency since 1979. The most extreme humid heat is highly localized in both space and […]

Amazon rainforest could be gone within a lifetime

Science Daily  March 10, 2020 Regime shifts can abruptly affect hydrological, climatic and terrestrial systems, leading to degraded ecosystems and impoverished societies. Researchers in the UK analysed empirical data from terrestrial, marine and freshwater environments and show positive sub-linear empirical relationships between the size and shift duration of systems. Each additional unit area of an ecosystem provides an increasingly smaller unit of time taken for that system to collapse, meaning that large systems tend to shift more slowly than small systems but disproportionately faster. They substantiated these findings with five computational models that reveal the importance of system structure in […]

Atmospheric river storms create $1 billion-a-year flood damage

Science Daily  December 4, 2019 Researchers found that flooding has caused nearly $51 billion in damages to western states in the last 40 years. More than 84 percent of these damages were caused by atmospheric rivers (ARs), long narrow corridors of water vapor in the atmosphere, capable of carrying more than twice the volume of the Amazon river through the sky. A team of researchers in the US (UC San Diego, US Army) used 40 years of data from the National Flood Insurance Program to show that ARs are the primary drivers of flood damages in the western United States. […]

Nine climate tipping points now ‘active,’ warn scientists

Science Daily  November 27, 2019 According to an international team of researchers (UK, Germany, Sweden, Denmark, Australia) the evidence from tipping points alone suggests that we are in a state of planetary emergency: both the risk and urgency of the situation are acute. They summarize evidence on the threat of exceeding tipping points, such as the loss of the Amazon rainforest or the West Antarctic ice sheet, identify knowledge gaps and suggest how these should be plugged. They explore the effects of such large-scale changes, how quickly they might unfold and whether we still have any control over them. According […]

How Dust Could Have Brought About The Collapse of a Once Mighty Empire

Science Alert  October 28, 2019 New research by an international team of researchers (Japan, Germany) suggests that the Akkadian Empire, based around the city of Akkad in ancient Mesopotamia, may have been brought low by a more unusual cause: dust storms. Fossil samples are windows in time showing that variations in climate significantly contributed to the empire’s decline. Meteorological conditions together, and a harsh environment for growing crops appears, one that most likely lead to civil unrest and societal collapse. All of which means a greater insight not just into the past, but into the changing climate conditions today. Just […]