1. Representing Climate Data
Part I
Maps and Numbers
Representing Climate Data

2. Station Models
Isoline Maps
Satellite Images

3. Station model: an abbreviated plot of weather station data

4. Station model: abbreviation of weather station data

7. Current weather map

8. Station model: (p. 411, textbook)
Pressure (without decimal point; without initial 10 or 9)(mb)
Air Temperature
Cloud
cover
pressure change in past 3 hrs (without decimal pt)
Present weather
Dew point
Wind direction
Wind speed

10. Wind direction Direction arrow points is wind direction
(direction wind is coming FROM)
If calm, no arrow and
double circle

11. Wind speed

12. “knot”
Nautical mile per hour
1 knot = 1.15 mph; 1.9 km/hr

13. Current pressure 162 = 1016.2 mb 3 numbers; in mb; no decimal point;
10 or 9 at beginning of number is NOT shown
162
Does number begin with
“10” or “9” ?
162 = mb

14. 353 ? mb
175? mb
985?
998.5 mb
893?
989.3 mb
074? mb
890?
989 mb

15. Pressure tendency during past three hours
Amount of change; mb;
No decimal shown; 02

16. 07 13

17. Current surface analysis

18. Isoline maps
Interpolate between discrete data points to create a continuous “surface”:
Helps us to visualize the data
examples:
Elevation surface
Pressure surface
Temperature surface

19. Topographic map an elevation surface
Contour lines

20. Temperature map 20 30
isotherms 40 50 50 60

21. Isotherm map

22. Pressure surface
isobars

23. All data values on an isoline are equal.
The interval between lines is constant for the entire map. 50 40 52 45 50 39 60 43 60 70 64 69 58

24. Trough: line of relatively low values
(Isolines point to higher values)
Ridge: line of relatively high values
(Isolines point toward lower values)
Terms usually used on pressure maps

31. Isotherm map

32. Current weather map

33. Gradient Steep/strong gradient: close isolines
Weak gradient: widely spaced isolines

34. 500 miles H L
1004
1020
1006
1008
1010
1018
1014
1012
1016