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Global population hit by extreme drought set to double

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Available freshwater is on track to decline sharply across two-thirds of Earth’s land surface toward the end of the century mostly due to climate change, with the number of people exposed to extreme drought doubling, researchers have reported. 

Even under a scenario of moderate decline in greenhouse gas emissions, land area scorched by extreme to exceptional drought conditions increases from three to seven percent, while the population at risk jumps from 230 million to about 500 million, they reported Monday in Nature Climate Change.

Projected shortfalls of water were “especially alarming” in Amazon River basin, Australia, southern Africa, the Mediterranean region, and parts of the United States, lead author Yadu Pokhrel of Michigan State University told AFP

Globally, one in 12 people could face severe water shortages every year by 2100, compared to an average of about one in 33 at the end of the 20th century.

“These declines in water storage and increases in future droughts are primarily driven by climate change, not land-water management activities such as irrigation and groundwater pumping,” Pokhrel said.

Humanity has been stalked by the deadly spectre of drought long before carbon emissions from burning fossil fuel caused global warming.

But observational data on Earth and from satellites has left no doubt that climate change is boosting their duration and intensity.

The possible consequences came sharply into view when reservoirs supplying Cape Town, South Africa — a city of 3.7 million — ran dry in early 2018 after a multi-year drought, giving rise to the term “Day Zero” when water runs out.

Global warming to date — just over one degree Celsius since the mid-19th century — enhances the likelihood of such droughts around Cape Town by a factor of three, earlier research has shown.

Allowing temperatures to increase another degree to 2C above pre-industrial levels would triple the risk again.  

Mexico City is currently facing a water crisis, and California has been coping with a lack of rain for most of the last decade. 

“There are growing concerns that many regions of the world will face water crises like these in the coming decades,” Pokhrel and colleague Farshid Felfelani said in a commentary published in The Conversation.

Pokhrel and an international team of two dozen hydrologists and engineers calculated for the first time the future impact of climate change on so-called terrestrial water storage (TWS), which is the total of all water stored or available on land.

Earlier projections of drought and changes in water availability have been based mostly on river flows, and only provide a partial picture.

“Understanding the risks ahead requires looking at the entire landscape of terrestrial water storage — not just rivers, but also water stored in soils, groundwater, snowpack, forest canopies, wetlands, lakes and reservoirs,” Pokhrel explained.

The researchers used a basket of hydrological models along with terrestrial water storage data from NASA’s twin Gravity Recovery and Climate Experiment (GRACE) satellites, which operated for 15 years up to 2017. 

To assess the impact of climate change, the scientists ran the data through two climate scenarios from the UN’s Intergovernmental Panel on Climate Change (IPCC). 

One assumes that humanity ratchets down CO2 and methane emissions enough to cap global warming below two degrees Celsius, in line with the 2015 Paris Agreement. The other assumes a slower reduction in carbon pollution.

Under the first, more optimistic scenario, moderate to severe droughts increase to mid-century and then stabilise. Very extreme water-shortage droughts, however, continue to escalate in frequency.

Under the second scenario, known as RCP6.0, “people living under extreme and exceptional droughts could more than double by 2100, increasing from three percent in the recent past to eight percent,” said Pokhrel.  

Source: https://tuoitrenews.vn/news/international/20210113/global-population-hit-by-extreme-drought-set-to-double/58757.html

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Aftershock rocks Indonesia quake zone as search continues

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JAKARTA — An aftershock hit Indonesia’s Sulawesi island on Saturday as rescue workers searched for people trapped under rubble after an earthquake killed at least 45 people, injured hundreds and sent thousands fleeing in terror.

Indonesia’s disaster mitigation agency said no damage or casualties were reported from the magnitude 5.0 aftershock in the West Sulawesi districts of Mamuju and Majene a day after the magnitude 6.2 earthquake.

Agency head Doni Monardo told Kompas TV the search continued for victims who could still be trapped under rubble.

More than 820 people were injured and about 15,000 people have been evacuated, the agency said.

Some have sought refuge in the mountains, while others went to cramped evacuation centres, witnesses said.

Indonesian Health Minister Budi Gunadi Sadikin visit injured people following an earthquake in Mamuju, West Sulawesi province, Indonesia, January 16, 2021 in this photo taken by Antara Foto. Photo: Reuters
Indonesian Health Minister Budi Gunadi Sadikin visit injured people following an earthquake in Mamuju, West Sulawesi province, Indonesia, January 16, 2021 in this photo taken by Antara Foto. Photo: Reuters

Friday’s quake and its aftershocks damaged more than 300 homes and two hotels, as well as flattening a hospital and the office of a regional governor, where authorities told Reuters several people had been trapped.

Access to the neighbouring city of Makassar remains cut off, Arianto Ardi of the search and rescue agency in Mamuju told Reuters, adding that the search will focus on the hotels.

Locals who fled to higher ground are seen at a temporary shelter following an earthquake in Mamuju, West Sulawesi province, Indonesia, January 16, 2021 in this photo taken by Antara Foto. Photo: Reuters
Locals who fled to higher ground are seen at a temporary shelter following an earthquake in Mamuju, West Sulawesi province, Indonesia, January 16, 2021 in this photo taken by Antara Foto. Photo: Reuters

Dwikorita Karnawati, the head of Indonesia’s meteorology and geophysics agency, told Metro TV on Saturday that another quake was possible and could reach a magnitude of 7.0, urging residents to keep out of the water because of the tsunami risk.

The earthquake magnitude scale is logarithmic; a one-point increase means it is 10 times bigger.

An aerial picture shows a hospital building collapsed following an earthquake in Mamuju, West Sulawesi, Indonesia, January 16, 2021 in this photo taken by Antara Foto. Photo: Reuters
An aerial picture shows a hospital building collapsed following an earthquake in Mamuju, West Sulawesi, Indonesia, January 16, 2021 in this photo taken by Antara Foto. Photo: Reuters

The difference in energy released is even greater. Straddling the so-called Pacific Ring of Fire, Indonesia is regularly hit by earthquakes.

In 2018, a devastating 6.2-magnitude quake and subsequent tsunami struck the city of Palu, in Sulawesi, killing thousands.

Source: https://tuoitrenews.vn/news/international/20210116/aftershock-rocks-indonesia-quake-zone-as-search-continues/58821.html

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South African scientists discover new chemicals that kill malaria parasite

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JOHANNESBURG — South African scientists have discovered chemical compounds that could potentially be used for a new line of drugs to treat malaria and even kill the parasite in its infectious stage, which most available drugs do not.

The research led by the University of Pretoria, published in the Nature Communications journal this week, found that chemical compounds undergoing trials for the treatment of tuberculosis and cancer — the JmjC inhibitor ML324 and the antitubercular clinical candidate SQ109 — can kill the disease-causing parasite at a stage when it normally infects others.

The World Health Organisation said in November that deaths from malaria due to disruption during the coronavirus pandemic to services designed to tackle the mosquito-borne disease will far exceed those killed by COVID-19 in sub-Saharan Africa.

Malaria killed more than 400,000 people across the world in 2019, according to the latest WHO figures, all but a few thousand of them in Africa.

There were 229 million cases across the world, 215 million of them on the continent.

“Our innovation was around finding compounds that are able to block the transmissible stages and we if we are able to do so then we stop the spread of malaria,” Research Chair in Sustainable Malaria Control and biochemistry professor Lyn-Marie Birkholtz, who was part of the team, told Reuters on Friday.

Most drugs kill malaria as it gets established in the liver or after it has infected red blood cells, but cannot tackle it once the parasite is released from the cells, which is when it is transmissible to other people via mosquito bites, she said.

The one drug that can have an effect during the transmissible phase, primaquine, is not widely used, owing to concerns about side effects.

“If we can develop these compounds … then we have an additional new tool that we can use to eliminate malaria,” said Birkholtz.

More tests would still need to be carried out before the compounds could be approved as a treatment for malaria but the breakthrough would also address concerns over drug resistance, she said.

Source: https://tuoitrenews.vn/news/international/20210116/south-african-scientists-discover-new-chemicals-that-kill-malaria-parasite/58816.html

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Global COVID-19 death toll tops 2 million

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The worldwide coronavirus death toll surpassed 2 million on Friday, according to a Reuters tally, as nations around the world are trying to procure multiple vaccines and detect new COVID-19 variants.

It took nine months for the world to record the first 1 million deaths from the novel coronavirus but only three months to go from 1 million to 2 million deaths, illustrating an accelerating rate of fatalities. 

So far in 2021, deaths have averaged over 11,900 per day or one life lost every eight seconds, according to a Reuters tally.

“Our world has reached a heart-wrenching milestone,” United Nations chief Antonio Guterres said in a video statement.

“Behind this staggering number are names and faces: the smile now only a memory, the seat forever empty at the dinner table, the room that echoes with the silence of a loved one,” he said, calling for more global coordination and funding for the vaccination effort.

By April 1, the global death toll could approach 2.9 million, according to a forecast from the Institute for Health Metrics and Evaluation. 

Given how fast the virus is spreading due to more infectious variants, the World Health Organization (WHO) warned the worst could be ahead.

“We are going into a second year of this. It could even be tougher given the transmission dynamics and some of the issues that we are seeing,” Mike Ryan, the WHO’s top emergencies official, said during a Wednesday event.

The United States has the highest total number of deaths at over 386,000 and accounts for one in every four deaths reported worldwide each day.

The next worst-affected countries are Brazil, India, Mexico and the United Kingdom.

Combined, the five countries contribute to almost 50 percent of all COVID-19 deaths in the world but represent only 27 percent of the global population. 

Europe, the worst-affected region in the world, has reported over 615,000 deaths so far and accounts for nearly 31 percent of all COVID-related deaths globally.

In India, which recently surpassed 151,000 deaths, vaccinations are set to begin on Saturday in an effort that authorities hope will see 300 million high-risk people inoculated over the next six to eight months.

Source: https://tuoitrenews.vn/news/international/20210116/global-covid19-death-toll-tops-2-million/58815.html

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