1 / 24

Lecture 3

Lecture 3. Vertical Structure of the Atmosphere. Average Vertical Temperature profile. Atmospheric Layers. Troposphere On average, temperature decreases with height Stratosphere On average, temperature increases with height Mesosphere Thermosphere. Lapse Rate.

akando
Télécharger la présentation

Lecture 3

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Lecture 3 Vertical Structure of the Atmosphere

  2. Average Vertical Temperature profile

  3. Atmospheric Layers • Troposphere • On average, temperature decreases with height • Stratosphere • On average, temperature increases with height • Mesosphere • Thermosphere

  4. Lapse Rate • Lapse rate is rate that temperature decreases with height

  5. Soundings • Actual vertical temperature profiles are called soundings • A sounding is obtained using an instrument package called a radiosonde • Radiosondes are carried aloft using balloons filled with hydrogen or helium

  6. http://www.srh.noaa.gov/mob/balloon.shtml Radiosonde

  7. Application: Reduction to Sea Level(See Ahrens, Ch. 6) proportional to weight of this column of air Surface pressure also called station pressure (if there is a weather station there!) Surface pressure here

  8. Math Obtained by integrating the hydrostatic equation from the surface to top of atmosphere.

  9. Deficiencies of Surface Pressure • Spatial variations in surface pressure mainly due to topography, not meteorology

  10. Height contours on topographic map Units: m It’s a mountain! 1050 1000 950 900

  11. Put a bunch of barometers on the mountain.

  12. Surface pressure (approximately) Units: hPa 885 890 895 900 Isobar pattern looks just like height-contour pattern!

  13. “Reduction to Sea Level” is proportional to weight of this column of air Let T = sfc. temp. (12-hour avg.) Surface pressure here For sea level pressure add weight of isothermal column of air temp = T. Sea Level

  14. Pressure as Vertical Coordinate • Pressure is a 1-1 function of height • i.e., a given pressure occurs at a unique height • Thus, the pressure can be used to specify the vertical position of a point

  15. At what height is the pressure equal to p? Given p

  16. Pressure Surfaces • Let the pressure, p1, be given. • At a given instant, consider all points (x, y, z) where p = p1 • This set of points defines a surface

  17. z p = p1 z(x2) z(x1) x x1 x2

  18. Height Contours Heights indicated in dekameters (dam) 1dam = 10m

  19. Two Pressure Surfaces z p = p2 z2 z2 – z1 z1 p = p1

  20. Thickness • z2 – z1 is called the thickness of the layer • Hypsometric equation  thickness proportional to mean temperature of layer

  21. Thickness Gradients z p = p2 Large thickness Small thickness warm Cold p = p1

  22. Exercise • Suppose that the mean temperature between 1000 hPa and 500 hPa is -10C. • Calculate the thickness (in dam)

  23. Repeat, for T = -20C

  24. Thickness Maps

More Related