<div class="eI0">
  <div class="eI1">Modelo:</div>
  <div class="eI2"><h2><a href="http://www.meteofrance.fr/" target="_blank" target="_blank">Arp&egrave;ge</a>(Action de Recherche Petite Echelle Grande Echelle) from Meteo France</h2></div>
 </div>
 <div class="eI0">
  <div class="eI1">Actualiza&ccedil;&atilde;o:</div>
  <div class="eI2">4 times per day, from 08:00, 14:00, 20:00, and 00:00 UTC</div>
 </div>
 <div class="eI0">
  <div class="eI1">Greenwich Mean Time:</div>
  <div class="eI2">12:00 UTC = 12:00 WET</div>
 </div>
 <div class="eI0">
  <div class="eI1">Resolution:</div>
  <div class="eI2">0.1&deg; x 0.1&deg; (Europa)<br>
  0.5&deg; x 0.5&deg;</div>
 </div>
 <div class="eI0">
  <div class="eI1">par&acirc;metro:</div>
  <div class="eI2">Geopotential in 850 hPa (solid, black lines) and Vorticity advection in 10<sup>5</sup>/(s*6h) (colored lines)</div>
 </div>
 <div class="eI0">
  <div class="eI1">Descri&ccedil;&atilde;o:</div>
  <div class="eI2">
The two types of vorticity advection are positive (PVA) and negative vorticity
advection (NVA). <img border="0" src="//www.weatheronline.pt/daten/expertgifs/v_adv_en.jpg" align="left">
The closed circles in the figure show the 850 hPa absolute vorticity
lines, the others the 850 hPa height lines. When an air parcel is moving from
an area higher vorticity to an area lower vorticity this is called: PVA
(red color). The other way around is called: NVA (blue color). PVA is
associated with upper-air divergence, i.e. upward vertical motion. NVA
is associated with down ward vertical motion. Therefore, PVA&nbsp; at 500
hPa is strongest above a surface low, while NVA at 500 hPa is strongest
above a surface high. <br>
In operational meteorology Vorticity advection maps are used to identify areas 
with vertical air motion to see where clouds, precipitation or clear conditions 
are likely to occur. Keep in mind, however, that PVA is not the same as upward
vertical motion. Here temperature advection is important too.<br>

    
  </div>
 </div>
 <div class="eI0">
  <div class="eI1">Arp&egrave;ge:</div>
  <div class="eI2"><a href="http://www.cnrm.meteo.fr/spip.php?article121/" target="_blank">Arp&egrave;ge</a> <br>
ARPEGE uses a set of primitive equations with a triangular spectral truncation on the horizontal, with a variable horizontal resolution, with a finite elements representation on the vertical and a “sigma-pressure” hybrid vertical coordinate. It also utilizes a temporal two time level semi-implicit semi-lagrangian scheme. The horizontal resolution of the ARPEGE model is around 7.5km over France and 37km over the Antipodes. It has 105 vertical levels, with the first level at 10m above the surface and an upper level at around 70km. Its time step is of 360 seconds.</br>
</div></div>
 <div class="eI0">
  <div class="eI1">NWP:</div>
  <div class="eI2">A previs&atilde;o num&eacute;rica do tempo usa o estado instant&acirc;neo da atmosfera como dados de entrada para modelos matem&aacute;ticos da atmosfera, com vista &agrave; previs&atilde;o do estado do tempo.<br>
Apesar dos primeiros esforços para conseguir prever o tempo tivessem sido dados na d&eacute;cada de 1920, foi apenas com o advento da era dos computadores que foi possível realiz&aacute;-lo em tempo real. A manipulaç&atilde;o de grandes conjuntos de dados e a realizaç&atilde;o de c&aacute;lculos complexos para o conseguir com uma resoluç&atilde;o suficientemente elevada para produzir resultados úteis requer o uso dos supercomputadores mais potentes do mundo. Um conjunto de modelos de previs&atilde;o, quer &agrave; escala global quer &agrave; escala regional, s&atilde;o executados para criar previsões do tempo nacionais. O uso de previsões com modelos semelhantes ("model ensembles") ajuda a definir a incerteza da previs&atilde;o e estender a previs&atilde;o do tempo bastante mais no futuro, o que n&atilde;o seria possível conseguir de outro modo.<br>
<br>Contribuidores da Wikip&eacute;dia, "Previs&atilde;o num&eacute;rica do tempo," Wikip&eacute;dia, a enciclop&eacute;dia livre, <a href="http://pt.wikipedia.org/w/index.php?title=Previs%C3%A3o_num%C3%A9rica_do_tempo&amp;oldid=17351675" target="_blank">http://pt.wikipedia.org/w/index.php?title=Previs%C3%A3o_num%C3%A9rica_do_tempo&oldid=17351675</a> (accessed fevereiro 9, 2010). <br>
</div></div>
</div>