![]() ![]() Inland surface waters are immediately affected by warming due to the strong correlation between air and surface water temperatures 2 and the impact of increased solar radiation 3. ![]() Global warming changes physical and chemical properties of lakes and catchments 1, as well as their biota 2. Thus, intended fertilizations are highly questionable, as hypolimnetic nutrients will become available during future natural or artificial turnovers. By simulating holomixis in experiments, we could induce significant vernal algal blooms, confirming that there would be sufficient hypolimnetic phosphorus which presently accumulates due to reduced export. We show that repeated lack (since 1977) and complete stop (since 2013) of holomixis caused drastic epilimnetic phosphorus depletions and an absence of phytoplankton spring blooms in Lake Zurich (Switzerland). However, nutrient inputs are essential for algal spring blooms acting as boost for annual food web successions. Reduced mixis impedes down-welling of oxygen rich epilimnetic (surface) and up-welling of phosphorus and nitrogen rich hypolimnetic (deep) water. Rising air temperatures strengthen thermal stabilization of water columns which prevents thorough turnover (holomixis). Here we show that recent re-oligotrophication processes indeed accelerated, however caused by lake warming. This caused speculations that restoration was overdone and intended fertilizations are needed to ensure ecological functionality. In line with reduced phosphorus and nitrogen loadings, total organismic productivity decreased and lakes have now historically low nutrient and biomass concentrations. Original article on Live Science.After strong fertilization in the 20 th century, many deep lakes in Central Europe are again nutrient poor due to long-lasting restoration (re-oligotrophication). Follow Live Science, Facebook & Google+. The study was published in the February 2015 issue of the Journal of Volcanology and Geothermal Research. He is planning to take his next trip to Yellowstone this fall, and he hopes further measurements will help shed light on the mysterious geological processes hidden deep below the surface. Some geysers interact with one another in peculiar ways some geysers are sensitive to earthquakes hundreds of miles away (while others are not), and some even soak up water from underground magma, Manga said. "Geysers come in a wide range of flavors and sizes and styles," Manga said. The environmental conditions are changing, and yet the geysers are perfectly regular. "There are all kinds of pathways and cracks, all kinds of places where steam can accumulate," Manga said. There are still basic questions the team has yet to answer, however, like why some geysers are so faithful. And it's those small nooks and crannies in the underground plumbing that first trap steam before bubbling it out slowly to heat the water column above. The new research finally settles the controversy, demonstrating that water does, in fact, boil from the top downward. "There has been controversy in the literature about whether boiling happens at the top or bottom," he said. As such, the column boils from the top downward, spewing water and steam hundreds of feet into the air.Īlthough Robert Bunsen - the first geologist to take pressure and temperature measurements inside a geyser, in Iceland -was the first to postulate this pattern in 1846, subsequent studies at Yellowstone and elsewhere, found the opposite, Manga said. This boiling reduces pressure on the water below, allowing that water to boil as well. Specifically, they found a series of loops and side chambers hidden deep below the surface that allows water to boil first at the top. They found that geysers seem to require a "special geology where steam can accumulate," Manga told Live Science. ![]() This heats liquid in a glass tube, allowing it to erupt periodically - though it doesn't erupt as regularly as the real one, nor is it accompanied by that awful smell. At the bottom of the device, there's a hot plate to simulate the hot rock deep underground. Manga and his students were able to use the images to recreate a model of El Jefe via a loop-de-loop apparatus in the lab. ![]()
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