That approach sweeps through data collected by weather stations, satellites and ocean-based equipment to project trajectories of global heat, air and vapor trails. The basis of weather forecasting for decades has relied on NWP (Numerical Weather Prediction) formulas, complex physics-based equations covering massive numbers of variables. The model, GraphCast, "significantly outperforms the most accurate operational deterministic systems on 90% of 1,380 verification targets," Lam said. In an article published in Science, Remi Lam, a staff research scientist at DeepMind, said their program is faster and more accurate than current forecasting methods and can precisely pinpoint characteristics such as air pressure, temperature, humidity and wind up to 10 days in advance. Google DeepMind researchers this week unveiled a highly accurate AI-based weather prediction model they say marks "a turning point in weather forecasting." The learned message-passing over the different meshes’ edges happens simultaneously, so that each node is updated by all of its incoming edges. It contains the set of nodes from M 6 and all the edges from M 0 to M 6. ( G) The multi-mesh is derived from icosahedral meshes of increasing resolution, from the base mesh ( M 0, 12 nodes) to the finest resolution ( M 6, 40,962 nodes), which has uniform resolution across the globe. ( F) The Decoder component maps the processed multi-mesh features (purple nodes) back onto the grid representation (red, downward arrows which terminate at a red box). ( E) The Processor component updates each multi-mesh node using learned message-passing (heavy blue arrows that terminate at a node). ( D) The Encoder component of the GraphCast architecture maps local regions of the input (green boxes) into nodes of the multi-mesh graph representation (green, upward arrows which terminate in the green-blue node). ( C) A forecast is made by iteratively applying GraphCast to each previous predicted state, to produce a sequence of states which represent the weather at successive lead times. ( B) GraphCast predicts the next state of the weather on the grid. Yellow layers in the closeup pop-out window represent the 5 surface variables, and blue layers represent the 6 atmospheric variables that are repeated at 37 pressure levels (5 + 6 × 37 = 227 variables per point in total), resulting in a state representation of 235,680,480 values. In the case of snowfall, the total precipitation is given in centimetres.Model schematic.( A) The input weather state(s) are defined on a 0.25° latitude-longitude grid comprising a total of 721 × 1440 = 1,038,240 points. If the precipitation falls as water or sleet, the total precipitation is given in millimetres. The total precipitation is given in inches. For example in temperatures just above freezing, snowfall with the water content of 10 millimetres of water forms a snow layer 10 centimetres thick on the ground, but in temperatures around -20 degrees Celsius the layer formed by same amount of water is 20 centimetres thick. If the water content of the rain is kept constant, the colder the weather, the thicker a layer the falling snow forms on the ground.įor example in temperatures just above freezing, snowfall with the content of a quarter of an inch of water forms a 2,5 inches thick layer of snow on the ground, but in temperatures around -5 degrees Fahrenheit the same amount of water forms a layer of snow 5 inches thick. Temperatures also affect how much a given amount of snowfall grows the amount of snow on the ground. These factors cause the amount of snow on the ground to grow less than the snowfall amount. The total snowfall refers to the snowfall from the cloud and does not take into account local melting, packing or drifting of snow. The total precipitation forecast gives the expected total precipitation for the whole 24-hour day. Please note that especially in inland locations wind gusts can be up to 1,5 to 2,5 times stronger than the 10-minute average wind speed. The wind forecast shows the strongest expected 10-minute average wind speed of the day. Unlike the daily weather symbol, the temperatures, wind information and total precipitation take into account the whole 24-hour day. Daily temperatures, wind information and total precipitation The cloudiness on the daily weather symbol is calculated as a weighted average of the predicted cloudiness of that day, with most weight assigned to the afternoon hours. You can see the more precise timing and intensity of the rain in the hourly forecast. The rain can be light rain that falls for a longer time period, or a heavy rain of short duration. The amount of rain drops on the daily weather symbol represent the total precipitation amount of that day. The weather in the evening or night time do not show on the symbol. The daily weather symbol gives an overview of the weather between 7 a.m.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |