Hawaii Weather Analysis Lab

Transcription

1 Hawaii Weather Analysis Lab Name Hawaii Pressure and Temperature Profiles 1. Plot profiles of temperature and relative humidity above using the underlined rawinsonde data. 2. On the diagram, draw a mountain representing Mauna Kea (4200 meters high). 3. What is the air pressure at sea level? Mauna Kea summit? 4. About ½ of Earth s atmosphere (500 mb) is below about what altitude? 5. About what is the temperature difference between Hilo and the summit of Mauna Kea on this day? 6. The layer in which the temperature increases is called the trade wind inversion. How much did the temperature increase in this layer on this day? 7. On the diagram, draw a cloud between 600 meters and the base of the inversion. 8. Haleakala is 3055 meters high. Do you think you can look down upon the cloud tops from the top of Haleakala on this day?

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3 Drawing isobar maps from surface pressure measurements 9. Using the surface pressure values given below, draw isobars for every ten (10) millibars of pressure. Identify any High (with a big H) or Low (with a big L) pressure centers on the map. A pressure center is identified by closed isobars, meaning that the isobars form a closed loop, perhaps in the shape of a circle, oval, or triangle.

4 Drawing isobar maps from surface pressure measurements 10. Using the surface pressure values given below, draw isobars for every five (5) millibars of pressure. Identify any High (with a big H) or Low (with a big L) pressure centers on the map. A pressure center is identified by closed isobars, meaning that the isobars form a closed loop, perhaps in the shape of a circle, oval, or triangle.

5 Pressure and Wind Direction 11. Draw arrows (lots and lots of arrows over the entire map) to indicate the estimated wind direction for this area of the Pacific. 12. What is the sea level pressure in Hilo? 13. What is the general direction of the winds over the Hawaiian Islands? (Note: winds are named by the direction they come FROM) 14. This is a normal trade wind pattern for Hawaii. Describe what you think the weather is like in Hawaii on this day.

6 Pressure and Wind Direction 15. Draw arrows (lots and lots of arrows over the entire map) to indicate the estimated wind direction for this area of the Pacific. 16. What is the general direction of the winds over the Hawaiian Islands? Are these normal trade winds? 17. What is the sea level pressure in Hilo? In Lihue, Kauai? 18. Is the pressure gradient greater over the Big Island or over Kauai? (Note: pressure gradient is greater when isobars are closer together). 19. Over which island do you think the winds are strongest? (Note: higher pressure gradient causes stronger winds) 20. Which island do think most likely to get rain, Big Island or Kauai? (Note: rain is usually associated with low pressure centers)

7 Variation in wind direction Wind Roses Monthly percent Frequencies of Wind Directions for Honolulu. Month Wind Direction (% of wind winds from that direction) N NE E SE S SW W NW CALM February August For February, what is the total frequency of the 3 westerly components (SW, W, NW)? The 3 easterly components (NE, E, SE)? Which is larger and by how much (in %)? 22. For August, what is the total frequency of the 3 westerly components (SW, W, NW)? The 3 easterly components (NE, E, SE)? Which is larger and by how much (in %)? 23. Which month sees more frequent trade winds (E and NE)?? 24. Plot the frequencies given above in the two wind roses on the next page, using one diagram for each month. To plot the data, make a bar the length of each frequency extending in the proper direction. (For example, if the N frequency is 20%, make a bar extending directly upward from the center to the 20% circle). Also, write the percentage of calm days as a number in the center circle. After you finish plotting the wind roses, looked at the accompanying diagram of wind roses for the entire island chain, entitled Local Winds. 25. Compare the Lihue and Hilo wind roses. Both are on the windward sides of their islands. What is the most common wind direction in Hilo? Lihue? Why do you think they are different? 26. Compare the Kona Airport and Honolulu wind roses. Both are leeward locations. What is the most common wind direction in Honolulu? Kona Airport? Why do you think they are different?

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