Scientists begin to unravel summer jet stream mystery As the UK's official weather service the Met Office works closely with the media to ensure that the country is aware of, and can cope during, times of extreme weather. The Met Office Press Office provides journalists with accurate and reliable weather and climate information and resources for stories on TV and radio, in print, and online. Welcome to the Press Office, the Met Office's dedicated resource for journalists. The Press Office works closely with the UK's media to provide journalists with accurate and reliable weather and climate information and resources to support the nations enduring fascination with the weather. Here on the Press Office web pages you can find our latest news releases, news archive and the official blog of the Met Office press office. Together they provide journalists and bloggers with the latest weather, climate science and business news and information from the Met Office.
Flights probe jet stream role in floods A major international effort is under way to research one of the greatest unknowns in weather forecasting - the influence of the jet stream. For the first time, a fleet of drones and planes is being deployed from the United States, Iceland and Britain to investigate the flow of air crossing the Atlantic. Jet streams are powerful currents of high-altitude wind that govern the patterns of weather down on the surface. The one over the Atlantic has frequently driven storms over Britain, most recently last winter, causing devastating floods. Early results indicate that the jet stream is narrower, stronger and more sharply defined than predicted by computer models - which could have implications for weather forecasts. Although forecasting has improved massively in recent years, a particular kind of disturbance in the jet stream over America is blamed for about 100 late or inaccurate forecasts of extreme rainfall over Europe in the past decade. Pioneering flight Wobbling free Sharper and stronger
Dust Over the Arabian Sea October is a month of transition for weather patterns over the Arabian Sea. In the summer, winds blow from the sea toward land. In the winter, the winds reverse and blow over the Arabian Sea from the northeast. During October, between the summer and winter monsoons, the prevailing wind direction varies. When the Visible Infrared Imaging Radiometer Suite (VIIRS) on Suomi NPP satellite acquired this image on October 26, 2016, northeasterly winds were dominant and blew several dust plumes off the coast of Iran and Pakistan. NASA image by Jeff Schmaltz, LANCE/EOSDIS Rapid Response, using VIIRS data from the Suomi National Polar-orbiting Partnership satellite. Instrument(s): Suomi NPP - VIIRS
Foehn effect When air passes over mountains, the valleys on the downwind side (or 'lee' side) commonly experience strong and gusty downslope winds accompanied by abrupt warming and drying. These are known as foehn winds, and their warming and drying effect - the foehn effect - can be striking and far-reaching. What is the foehn effect? Foehn winds (sometimes written "Föhn") are common in mountainous regions, regularly impacting the lives of their residents and influencing weather conditions for hundreds of kilometres downwind. On 14-15 January 1972 in Montana, USA, a foehn Chinook event was responsible for the greatest temperature change over a 24 hour period ever recorded in the United States: according to the US National Weather Service the temperature rose a staggering 57 °C; from -48 to 9 °C. In the UK, the most notable foehn events tend to occur across the Scottish Highlands where the moist prevailing westerly winds encounter high ground along Scotland's west coast. Impacts of the foehn effect
Scientists say the global ocean circulation may be more vulnerable to shutdown than we thought The Gulf Stream carries warm water from the eastern coastline of the United States to regions of the North Atlantic Ocean. (NASA’s Goddard Space Flight Center) Intense future climate change could have a far different impact on the world than current models predict, suggests a thought-provoking new study just out in the journal Science Advances. The Atlantic meridional overturning circulation, or AMOC, is often described as a large oceanic conveyor belt. But some scientists have begun to worry that the AMOC isn’t accurately represented in current climate models. Nevertheless, the authors of the new study point out, many climate models assume a fairly stable AMOC — and that could be affecting the predictions they make for how the ocean will change under future climate change. Liu and colleagues from the UC-San Diego and the University of Wisconsin at Madison took a commonly used climate model and corrected for what they considered to be the AMOC stability bias. business energy-environment
*****Pressure: An interactive journey to the bottom of the sea Now we can all experience diving to the deepest point of the Mariana Trench, nearly 11,000m down into the depths of the ocean Fifty-seven years ago, Swiss engineer Jacques Piccard and US Navy Captain Don Walsh touched down at the very bottom of the sea – 10,911m (35,797ft) deep – in their specially-designed submarine, the Trieste. The location was Challenger Deep, a spot in the Mariana Trench, east of the Mariana Islands, the lowest known point in the entirety of the planet’s oceans. Named ‘Project Nekton’, the touchdown was the first time in human history that anyone had reached such depths. ‘Like a free balloon on a windless day,’ wrote Piccard, ‘indifferent to the almost 200,000 tons of water pressing on the cabin from all sides, balanced to within an ounce or so on its wire guide rope, slowly, surely, in the name of science and humanity, the Trieste took possession of the abyss, the last extreme on our Earth that remained to be conquered.’
Saharan dust causing hazy conditions | Loop News Trinidad and Tobago Reports of haziness over the weekend are the result of high winds which carry over mineral dust from the Saharan Desert, bringing with it hazy visibility and for some, respiratory problems. Meteorologist Jean-Marc Rampersad said to LoopTT that, although it is difficult to predict how long these conditions will last, if strong winds continue, chances are likely that the present hazy conditions will persist for up to 48 hours. He added that the strength and duration of hazy conditions depends on factors such as wind surge and wind direction over the Atlantic Ocean, which channels dust from the Sahara Desert on the African continent over to the Caribbean and parts of South America. The added dustiness may irritate those prone to respiratory conditions such as sinusitis or asthma. A forecast from the University of Athens showed the Trinidad and Tobago and parts of the Caribbean being affected by Saharan Dust, with a reported dust concentration of between one and 10 cubic metres.
Wind Map | Deck.gl Blog A few weeks ago I set on trying out new WebGL 2.0 features with deck.gl. WebGL 2.0 brings plenty of new goodies to be used for game development, creative coding and data visualization like instancing, floating-point textures, transform feedback, multiple render targets, and more. With this in mind, and inspired by the work of Cameron Beccario, Viegas and Wattenberg, and NASA, I created a WebGL 2.0 wind map demo using deck.gl. This interactive demo enables you to change the map’s perspective by using cmd + drag; toggle between vector field and particle layers on the left panel, and use the slider to change the time of day to see wind change for a 72 hour period. Some interesting insights The screenshot below shows wind speed near Mount Washington, which has the fastest winds in the US. Something interesting to look at as well are the wind corridors being formed in Florida at specific times. Under the hood The Delaunay Interpolation Layer The Vector Field Layer The Particle Layer And that’s it!
*****Fohn winds / Foen winds:Antarctica's troublesome 'hairdryer winds' Image copyright BAS It's an ill wind that blows no good - at least not for the ice shelves on the eastern side of the Antarctic Peninsula. A new study has found an atmospheric melting phenomenon in the region to be far more prevalent than anyone had realised. This is the foehn winds that drop over the big mountains of the peninsula, raising the temperature of the air on the leeward side well above freezing. "The best way to consider these winds is how they translate to german now, which is 'hairdryer' ('Foen')," explained Jenny Turton from the British Antarctic Survey (BAS). "So, they're warm and they're dry and they're downslope. Media playback is unsupported on your device The effect on the ice that pushes east from the Peninsula out over the Weddell Sea is clear. Such warm, downslope winds are well known across the Earth, of course; and they all have a local name. The chinook winds, for example, that drop over the Rockies and Cascades in North America are the exact same thing.
*****Thermohaline circulation: Climate Running AMOC | NRDC Thermohaline circulation (n.): deep ocean current driven by variations in salinity and temperature. I used to love watching the weather forecast when I was a kid, because I thought it was a cartoon. There were lots of colorful arrows going every which way and a man waving his arms like a snake charmer. I had no idea what any of it meant. Suddenly, I know more than I ever wanted to. The story begins with a stream of water called the Atlantic Meridional Overturning Circulation (AMOC), which runs from the tropics south of the equator to the North Atlantic. Since variations in temperature and salinity are responsible for the difference in density that powers the conveyor belt, scientists refer to the AMOC and similar currents as thermo- (heat) haline (salt). Oceanographers have always known that the speed of the AMOC’s conveyor belt changes, but they hadn’t detected a trend—until now. That weakening is probably both a cause and an effect of climate change. A snail-like AMOC is a big problem.
Radioactive 'pooh sticks' trace carbon's ocean journey Image copyright Getty Images Radioactive iodine from nuclear reprocessing plants in the UK and France has been detected deep in the waters near Bermuda. Scientists say the contaminants take a circuitous route travelling via the Arctic Ocean and down past Greenland. Researchers believe the radioactivity levels are extremely low and present no danger. However, scientists can use the iodine to accurately map the currents that transport greenhouse gases. One scientific consequence that arose from the testing of nuclear bombs in the atmosphere in the 1950s was that their radioactive fallout provided a powerful global tracer of water circulation and deep-ocean ventilation. Other sources of radioactive material for scientists to track water movements have been the nuclear reprocessing plants at Sellafield in the UK and at La Hague in France. Contaminants have been legally released from these sites for more than 50 years. The research has been presented at the Goldschmidt2017 conference in Paris.
Seeing global winds - Ocean Navigator - March/April 2014 Feb 28, 2014 by tim queeney The “earth” website by Cameron Beccario is an intriguing way to get a feel for global wind circulation. This view from “earth” shows winds high in the atmosphere. You’ve heard of working for peanuts, but how about for pickled herring? If you go to the site you’ll see why weather fans from pilots to fishermen to voyagers have embraced “earth.” The inspiration for “earth” was hint.fm/wind/, a site that displayed wind speeds across the U.S. using gridded binary (GRIB) data. “My previous job was working on stuff deep in the data center,” Beccario said. He also picked up a software tool called D3 that does geographic rendering of global map projections. The GRIB data used on the site is produced at the National Weather Service’s Environmental Modeling Center (EMC). The extensive list of map projections is a good indication that there are many ways to look at the data in “earth.” Edit Module