That wind earth site is awesome Robin. I can see two cyclones in the Indian Ocean. Apparently the one closer to Australia is Cyclone Bruce.
On 2013/Dec/19, at 12:42 PM, Robin Whittle wrote: > Here is a new addition to my collection of weather URLs: > > http://earth.nullschool.net/ > > I read about it at http://www.universetoday.com. It is a > javascript-driven, apparently very fluid, display of wind direction > anywhere on Earth, with data updated from various models every 3 hours. > There is also the ability to look back in time and to look forwards by > up to 24 hours. > > The "earth" thingo at the bottom opens up a menu from which various > settings can be selected, with the "about" link providing an > explanation. Settings can be stored in a URL: > > > http://earth.nullschool.net/#current/wind/isobaric/1000hPa/orthographic=-225.44,-36.35,416 > > It is evident that the jetstream at about 10km (250hPa) is very > different from winds at the surface. I don't understand how the > jetstream makes sense in terms of what I understand about Hadley cells: > > https://en.wikipedia.org/wiki/Hadley_cell > > On a day like today in Melbourne, at the western edge of a high pressure > system, I understand a significant amount of the heat we feel (predicted > maximum 40C) is due to hotter than normal, very dry, air piling up in > the troposphere after being transported there from the tropics. This is > in addition to air arriving from the inland north. This somehow > displaces air on the ground with dryer, hotter, air. If that's the > case, I am not sure how it works with the jetstream winds doing > something apparently unrelated (to my eyes) with the anticlockwise winds > at ground level which result from the high pressure system. > > My other weather links are: > > http://www.bom.gov.au/australia/charts/synoptic_bw.shtml > http://www.bom.gov.au/vic/forecasts/melbourne.shtml > http://www.bom.gov.au/vic/observations/melbourne.shtml > > http://www.bom.gov.au/products/IDR023.loop.shtml?looping=1&reloaded=0&topography=true&locations=true&range=true#skip > http://www.bom.gov.au/australia/satellite/ > http://www.bom.gov.au/jsp/watl/weather/obs.jsp?graph=all_obs&station=86068 > > The last one is for the nearby Viewbank weather station. This shows the > last few days of temperature and other measurements, including the dew > point. The dew point is a measure of the moisture content of the air. > When this drops suddenly, as it did a few hours ago, I understand (from > an explanation by a meteorologist) this is the dry Hadley cycle air > descending to ground level and somehow (I have no idea how) displacing > the more moist air which was previously at ground level. > > A final link, which is only for the Melbourne area is: > > http://www.baywx.com.au/melbtemp.html > > This page, one of several, shows the predicted minimum and maximum > temperatures with the observations filled in as the day progresses. > There's an archive of the graphs, which enabled me to generate > temperature graphs of the heatwave associated with the 2009 bushfires: > > https://en.wikipedia.org/wiki/Black_Saturday_bushfires > > https://commons.wikimedia.org/wiki/File:Melbourne-temp-2009-02-10.png > > https://commons.wikimedia.org/wiki/File:Melbourne-temp-2009-02-10-compact.png > > > I understand those dramatic peaks in temperature are driven largely by > Hadley cells. > > - Robin > > > > > > _______________________________________________ > Link mailing list > [email protected] > http://mailman.anu.edu.au/mailman/listinfo/link -- Kim Holburn IT Network & Security Consultant T: +61 2 61402408 M: +61 404072753 mailto:[email protected] aim://kimholburn skype://kholburn - PGP Public Key on request _______________________________________________ Link mailing list [email protected] http://mailman.anu.edu.au/mailman/listinfo/link
