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Daily Mail
3 days ago
- Business
- Daily Mail
Scientists are baffled as measurements reveal South Africa is RISING out of the ocean
Scientists have been baffled to discover that South Africa is rising out of the ocean. New measurements reveal that the country is rising by as much as two millimetres per year in some places. Previously, scientists thought this rapid uplift was due to a phenomenon called mantle flow - the movement of semi-molten rock beneath the Earth's crust. But a new study claims that climate change is actually to blame. Using a network of static GPS receivers dotted across the country, scientists made extremely precise measurements of South Africa's height. This revealed that the areas bulging upwards the most were the areas that had experienced the most severe water shortages. Co-author Dr Makan Karegar, from the University of Bonn, says: 'This data showed an average rise of six millimetres between 2012 and 2020. 'We believe that it [is] also possible that a loss of groundwater and surface water is responsible for the land uplift.' Thanks to South Africa's network of GPS receivers, known as the Global Navigation Satellite System (GNSS), scientists have known for some time that the country is rising. Scientists had assumed that this was caused by something called the Quathlamba hotspot. This huge, tube-like structure transports hot material from closer to the Earth's core towards the surface under the mantle. In theory, this movement of mass towards the surface could create a bulge that would cause the land to rise up. However, scientists from the University of Bonn have tested a new theory which they believe offers a better explanation. By comparing the GNSS data with factors like precipitation rates across the country, they found a clear parallel in the data. The areas that had suffered severe droughts all experienced a particularly pronounced increase in height. Although the Earth might seem solid from our perspective, on the planetary scale it behaves much more like a rubber ball. Co-author Christian Mielke, of the University of Bonn, told MailOnline: 'The total mass of surface water, soil moisture, and groundwater is so large that it deforms the Earth's crust - like putting pressure on an elastic ball. 'Droughts are associated with loss in these water storages. The loss of water mass due to the drought causes the Earth's crust to lift again. In their paper, published in the Journal of Geophysical Research: Solid Earth, the researchers argue this is now happening in South Africa. In addition to the GNSS and precipitation data, the researchers looked at data from the GRACE satellite mission - a joint project between NASA and the German Aerospace Center. Using sensitive equipment, this satellite measures subtle changes in the Earth's gravitational field in the ground below. Mr Mielke says: 'These results can be used to calculate, among other things, the change in the total mass of the water storage including sum of surface water, soil moisture and ground water.' Even though the GRACE satellite only has a resolution of several hundred kilometres, the data clearly showed that the lower the mass of water in a region, the higher the uplift measured by the GPS stations. In increasingly drought-stricken South Africa, the loss of water mass has been so pronounced that it has led to rapid increases in elevation. This rise was most pronounced between 2015 and 2019 during which South Africa faced one of its worst droughts in history. In that period, Cape Town, South Africa's capital and the continent's 10th largest city, lived under the impending threat of 'Zero Day' - a day without any water. As human-caused climate change leads to a hotter climate, droughts are becoming more common and more intense. For example, in 2022, scientists found that climate change made the droughts which struck the Northern Hemisphere over 20 times more likely to happen. Ultimately, the researchers believe the elevation changes in South Africa are more likely to be 'episodic' rather than permanent. 'The strong uplift we observed was mainly caused by water loss during the server drought years,' Mr Mielke adds. 'Outside of drought years, it is to expect that water reserves will replenish and land subsidence will occur. 'However, if it doesn't rain more often in future, the land could continue to rise on average until there is no more water.' The data shows that areas with the worst droughts (brown) were also the areas with the highest uplift (red triangles). This information could help scientists monitor water levels in real time using GPS data While Mr Mielke points out that this probably won't have any other consequences, it could provide a useful way to manage our warmer climate. If droughts and low water levels cause the ground to rise, scientists can use the data from the GPS system to get a real-time measurement of water reserves. This could allow scientists to measure the effects of droughts more precisely than ever before, using a method which is cheaper and easier than any other option. Given the ongoing threat of drought faced by South Africa, and many other countries including the UK, this could become a vital water management tool. WHAT CAUSED THE SUMMER 2018 GLOBAL HEATWAVE? There are several leading theories as to what caused the global heatwave, according to University of Reading climate scientist Professor Len Shaffrey. 1. Climate Change: Temperatures are increasing globally due to the burning of fossil fuels increasing concentrations of atmospheric carbon dioxide. The global rise in temperatures means that heatwaves are becoming more extreme. The past few years have seen some record-breaking temperatures in Europe, for example the 2015 heatwave and the 2017 'Lucifer' heatwave in Central Europe. Unusually warm summer temperatures have been recorded elsewhere, for example in Canada and Japan, and climate change is very likely to have played a role here as well. 2. North Atlantic Ocean Temperatures: Temperatures over the North Atlantic Ocean can play a role in setting the position of the jet stream, which in turn has a profound impact on the weather we experience in the UK and Ireland. This summer has seen relatively warm North Atlantic Ocean temperatures in the subtropics and cold ocean temperatures to the south of Greenland. These are thought to be influencing the high pressure over Europe and pushing the jet stream further northwards. 3. La Nina: Every few years, ocean temperatures in the Tropical Pacific swing between being relatively warm (known as El Nino) and cool (La Nina). Since October last year the Tropical Pacific has been in a La Nina phase. La Nina is sometimes associated with cold winters in North Western Europe (for example the winter of 2010/11 and the recent cold spell in March 2018). However, this year's La Nina had started to weaken around April and had almost gone by June when the current dry spell in the UK began. 4. It's the weather: The above factors influence type of the weather get in the UK and Ireland but good or bad luck also plays a role, especially for very unusual weather such as the current hot and dry spell. This summer is no different and the hot and dry weather is partly due a combination of North Atlantic Ocean temperatures, climate change and the weather. Should weather patterns continue as they are then we might expect this summer will turn out to be as hot and dry as the extreme summer of 1976.
Yahoo
4 days ago
- Health
- Yahoo
South Africa Is Rising Up Out of The Ocean, Scientists Reveal
As climate change intensifies, South Africa is not only becoming hotter and drier; it's also rising by up to 2 millimeters per year, according to a new study. Scientists knew this uplift was happening, but the prevailing explanation attributed it to mantle flow within Earth's crust beneath the country. The new study suggests the uplift is caused by recent droughts and the resulting loss of water, a trend linked to global climate change. The discovery emerged due to a network of global navigation satellite system (GNSS) stations in South Africa. Mainly used for atmospheric research, this network provides precise data on the height of various sites across the country. "This data showed an average rise of 6 millimeters between 2012 and 2020," says geodesist Makan Karegar from the University of Bonn. Experts had ascribed this phenomenon to the Quathlamba hotspot. A localized bulge in Earth's crust could form from the upswelling of material from a suspected mantle plume beneath the region, spurring the recent uplift. "However, we have now tested another hypothesis," Karegar says. "We believe it is also possible that a loss of groundwater and surface water is responsible for the land uplift." To explore this possibility, Karegar and his colleagues analyzed the GNSS height data along with precipitation patterns and other hydrological variables across regions of South Africa. A strong association stood out. Areas where severe droughts have occurred in recent years underwent an especially dramatic uplift of land. The rise was most pronounced during the 2015–2019 drought, a period when Cape Town faced the looming threat of "day zero" – a day with no water. The study also looked at data from the GRACE satellite mission, a joint effort by NASA and the German Aerospace Center to measure Earth's gravity field and changes in water distribution. "These results can be used to calculate, among other things, the change in the total mass of the water storage, including the sum of surface water, soil moisture, and groundwater," says University of Bonn geodesist Christian Mielke. "However, these measurements only have a low spatial resolution of several hundred kilometers." Despite this low resolution, GRACE satellite data supported the hypothesis: Places with less water mass had higher uplift at nearby GNSS stations. The team used hydrological models for higher-resolution insight into how droughts can influence the water cycle. "This data also showed that the land uplift could primarily be explained by drought and the associated loss of water mass," Mielke says. The researchers suggest that in addition to upward pressure from a mantle plume, the loss of moisture in the crust could also cause it to bulge. This is another example of the many ways climate change is tweaking the world around us, but it could also offer practical value. GNSS data, which are cost-effective and simple to collect, could offer a new way to track water scarcity, including critical groundwater resources – widely overexploited by humans for agriculture and other purposes. Given the dire threat droughts pose in South Africa, as well as many other parts of the world, this finding may provide a valuable window into water availability. The study was published in the Journal of Geophysical Research: Solid Earth. An Extreme Drop in Oxygen Will Eventually Suffocate Most Life on Earth The Ocean Is Getting Darker, Threatening All That Lives Within Your Salad Could Be Carrying Microplastics From Soil Into Your Body
Yahoo
5 days ago
- Health
- Yahoo
The land under South Africa is rising every year. We finally know why.
When you buy through links on our articles, Future and its syndication partners may earn a commission. Drought and water loss caused South Africa to rise an average of 6 millimeters (0.2 inches) between 2012 and 2020, according to a new study. Scientists have developed a new model to measure this land uplift and associated water loss using global positioning system (GPS) data. In South Africa, they found that uplift patterns correlated with droughts and with seasonal shifts between dry and wet seasons. The GPS-based model could help researchers spot signs of drought in the future, the researchers suggest. Scientists have known for more than a decade that South Africa is rising. Initially, some suspected the uplift was caused by a plume of hot rock in the mantle, Earth's middle layer, that sits beneath the country. A mantle plume forms when hot material from deep in the mantle rises and pushes against the lithosphere (the crust and upper mantle), lifting the land above it. But Makan Karegar, a geodesist at the University of Bonn in Germany, noticed that data showing uplift in South Africa correlated with periods of drought. In particular, Karegar and his colleagues spotted a pattern of uplift that corresponded to the intense "Day Zero" drought South Africa faced between 2015 and 2018, when the city of Cape Town was at risk of needing to shut off the municipal water supply. "We started to think there should be a link between this pattern and water loss," Karegar told Live Science. To investigate this relationship further, the team collected GPS data from permanent stations scattered throughout South Africa. These stations can precisely measure changes in height over time, down to fractions of a millimeter per year. In the new study, published April 9 in the Journal of Geophysical Research: Solid Earth, the scientists developed a model linking this uplift to changes in the country's water storage. Related: Africa is being torn apart by a 'superplume' of hot rock from deep within Earth, study suggests As water disappeared from surface reservoirs, soil, and groundwater reserves, the land rose, like memory foam does after a weight is removed. The researchers observed some regional and seasonal variations in height, as well as some long-term variability. But overall, between 2012 and 2020, South Africa rose an average of 6 mm in response to water loss, the team found. Some areas near depleted water reservoirs rose as much as 0.4 inches (10 mm) during the drought. "The biggest surprise for us was that we saw an uplift over most parts of South Africa," study coauthor Christian Mielke, a geodesist at the University of Bonn, told Live Science. "We were expecting that this would probably just affect regions close to cities," near where reservoirs are concentrated. Next, the team validated their model by comparing changes in land heights across South Africa to existing models of water storage and loss. They found that the GPS-based results agreed well with predictions of water loss based on satellite measurements and climate data. While the new study doesn't rule out potential contributions from the mantle plume beneath South Africa, the strong correlations with existing models of water storage suggest that water loss is the main driving force behind the uplift. This suggests that the uplift might not be permanent. With enough precipitation and water returning to reservoirs, the land could start to sink again, Karegar said. RELATED STORIES —Earth from space: Golden river of toxic waste spills out from deadly mining disaster in South Africa —Africa is being torn apart by a 'superplume' of hot rock from deep within Earth, study suggests —Severe drought helped bring about 'barbarian' invasion of Roman Britain, study finds But teasing out how long it might take for South Africa to rise or sink again will likely require more data, said Bill Hammond, a geodesist at the University of Nevada Reno who was not involved in the study. "We often don't know how long our current measurements are applicable for," he told Live Science. With just 30 years of GPS data from which to draw trends, many of which South Africa spent in drought conditions, it could be difficult to determine exactly how much of the uplift is due to drought versus the mantle plume, or how long it might take for the land to subside again after the drought's end, he added. In the meantime, using GPS measurements as a tool for monitoring drought conditions "is a major emerging approach," Karegar said. While South Africa's existing GPS stations are fairly spread out, stations in other parts of the world are spaced much more closely. Where these networks are established, they could help with water management, Karegar said.
BBC News
23-05-2025
- Science
- BBC News
Flowers have been blooming on Earth for 123 million years
The first flowers must have grown on Earth 123 million years ago according to from two universities in Germany, Leibniz University Hannover (LUH) and the University of Bonn, used pollen to find out when the very first flowering plants is very important because it can tell us a lot about the history of life on scientists used pollen from the earliest flowering plants in old layers of mud and sand in Portugal, which they've dated further back that was believed until now. How do you date pollen? Before this study, scientists thought a certain group of flowering plants called eudicots first showed up about 121 million years ago. Experts explained how this newly-dated pollen, along with pieces of plants, were washed by river water into an ancient ocean, which over time got buried in rock, mud and dirt, before being dug up and studied millions of years research was published in the scientific journal, Proceedings of the National Academy of Sciences. Why is this discovery important? When flower plants first began to grow is important because they make up most of the plants we see around us today - like flowers, fruit trees, and many of the crops humans and animals the flowering plants developed, and from which other older plants, remains a when flowering plants first appeared, they changed the variety of living things on Earth a lot - helping to created new homes and food for lots of different insects and Dr. Ulrich Heimhofer of the LUH Institute of Earth System Sciences says "The emergence of flowering plants altered the biological diversity considerably."So knowing exactly when these plants first showed up helps experts learn how life on Earth changed over time.
