Weather Troughs and Ridges.?

Question

What are some ways to indentify trougs and ridges on maps, and to know whether they are at the surface or in upper levels of the atmosphere?

Answer 1

Trough and Ridge Amplification
in response to lower level temperature advection

*When you look at troughs and ridges you usual look at 500mb maps(Go here and look at the "500mb Vort, Ht" section)
http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/namer/gfs/12/model_mu.shtml

Warm advection beneath an upper level ridge causes it to build (increase in amplitude), while cold advection beneath an upper level trough will contribute to its deepening. The animation below highlights the amplification of ridge/trough system at 250 mb in response to intense thermal advection at 850 mb



Here is a Trough. A trough is an elongated area of low atmospheric pressure that can occur either at the Earth's surface or at higher altitudes:
http://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/trough.rxml?hret=/guides/mtr/cyc/upa/amp.rxml

When the height contours bend strongly to the south, it is called a TROUGH. Strong troughs are typically preceded by stormy weather and colder air at the surface. Above is an example of a trough in an upper-level height field (red contours). The trough axis is denoted by the purple line.
A trough is an elongated area of low atmospheric pressure that can occur either at the Earth's surface or at higher altitudes.
Upper-level troughs influence many surface weather features, including the formation and movement of surface low pressure areas and the locations of clouds and precipitation. Precipitation tends to fall to the east of the trough axis while colder, drier air tends to prevail to the west of the trough. This happens because air rises to the east of troughs. As air rises, it cools, and its humidity begins condensing into clouds and precipitation. Air sinks on the west side of troughs, which inhibits clouds and precipitation. On weather maps of the Northern Hemisphere, troughs are shown by upper-air winds, or jet streams, blowing south and then turning back to the north. Strong upper-level troughs can be become negatively tilted and are associated with Arctic outbreaks and major snowstorms during winter. Surface low pressure areas tend to develop to the east of upper-level troughs in the rising air.


Here is a Ridge. A Ridge can occur both at the Earth's surface and at higher altitudes.
http://ww2010.atmos.uiuc.edu/(Gh)/wwhlpr/ridge.rxml?hret=/guides/mtr/cyc/upa/amp.rxml

When the height contours bend strongly to the north, this is known as a RIDGE. Strong ridges are accompanied by warm and dry weather conditions at the surface. Below is an example of a ridge in an upper-level height field (red contours). The purple line denotes the ridge axis.
Ridges, depending on their strength and how fast they move, can bring record summer heat and stifling air pollution to a region for several days. A ridge is an elongated area of high atmospheric pressure. They occur both at the Earth's surface and at higher altitudes. Upper level ridges can have a major impact on the weather at the surface. Sunny, dry weather usually prevails to the east of the upper-level ridge axis while cloudy, wet weather can dominate the weather picture to the west of the upper-level ridge axis. Air tends to sink to the east of the ridge axis, which inhibits clouds and precipitation. On the other hand, air tends to rise to the west of the ridge axis, which can lead to the formation of clouds and precipitation. Extremely hot weather during the summer and unusually mild weather during the winter are often associated with a strong, slow moving, upper-level ridge.
On Northern Hemisphere weather maps, upper-air ridges are shown by the path of upper altitude winds, or the jet stream, turning to flow northward and then back to the south.

Answer 2

Ridges And Troughs

Answer 3

Ridges are elongated higher height regions extending poleward, while troughs are elongated lower height regions extending equatorward. Generally when a meteorologist talks about troughs and ridges, they're talking about the upper levels.

Here's a labeled upper level chart.
http://www.theweatherprediction.com/charts/500/basics/17.jpg

Surface troughs and ridges occur as well, they're just elongated areas of low or high pressure rather than circular areas.

More often than not, a surface ridge will coincide with an upper ridge, and a surface trough will have an upper level trough nearby as well. There are some exceptions though.

Answer 4

Troughs And Ridges

Answer 5

This Site Might Help You.

RE:
Weather Troughs and Ridges.?
What are some ways to indentify trougs and ridges on maps, and to know whether they are at the surface or in upper levels of the atmosphere?

Answer 6

look at a 500 mb map...you can pull one of these up on the unisys website. troughs refer to upper level low pressure systems. ridges refer to upper level high pressure systems.

http://weather.unisys.com/

a trough is an area where there is a dip in the pressure lines
a ridge is an area where the pressure lines push upward

Answer 7

This is a very interesting topic

Answer 8

thanks for the answers everyone xx