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.

## Lecture 3

An Image/Link below is provided (as is) to download presentation Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. 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. 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

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

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

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

10. Put a bunch of barometers on the mountain.

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

12. “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

13. 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

14. 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

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

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

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

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

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

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

21. Repeat, for T = -20C

22. Thickness Maps

More Related