Meteo 003: Lab 4 Due Friday, September 22nd Chapter 4: 14ab, 15c Chapter 5: 10abd, 18 Chapter 6: 2ab, 7ab, 9acd Chapter 7: 9ab

4.14a,b pg. 163 Isohyets: isopleths of rainfall a) -same guidelines as all isopleths Hint: you’ll have to draw “circles” in places b) -prevailing winds are northeasterly -draw an arrow representing wind direction -air rises on windward side of a mountain

4.15c pg. 164 Heat Index/Apparent Temperature: the temperature the air “feels like” to a person when moisture is taken into account c) -temperature is in ᵒF -vapor pressure is in mb *note that the units do not work out, this is a simplified equation -when given dew point, substitute vapor pressure for equilibrium (or saturation, same thing) vapor pressure Be sure to read the first paragraph!!

Apparent Temperature Example Find the apparent temperature for a day given that the air temperature was 80ᵒF and the dew point was 70ᵒF. How do you find vapor pressure? Apparent Temperature = 80 + (25-16) = 89°F

5.10a,b,d pg. 205 a) -Which imagery is used to determine albedo? -High albedo = reflecting more, low albedo = absorbing more b) -Which imagery reveals information about temperature? -Refer to table on next slide d) -What is the relation between the amount of emitted radiation to cloud-top temperature? Then relate cloud-top temperature to the height of the cloud tops

Helpful Table Type of Imagery Visible Infrared Water Vapor Color Darker Lighter Interpretation Clearer Cloudier Warmer Colder Drier Moister

5.18 pg. 211 -Radar beams are sent out at an angle, and the earth is not flat! -For the snow showers to not be seen by the radar, what must be true?

6.2a,b pg. 243 Pressure Gradient Force: the force that directs air from higher toward lower pressure. *always points from high to low pressure *perpendicular to isobars (gets from high to low pressure fastest this way) -Think about when you’re pumping up a sports ball and air comes out a) -Wind blows away from higher pressure and toward lower pressure -Make sure to draw about a dozen arrows b) -Would the pressure gradient force be different in the Southern Hemisphere?

6.7a,b pg. 248 -Surface pressures at different locations with differing elevation need to be converted to sea-level pressure to be able to compare “apples to apples” -Pressure decreases with height in the atmosphere a) -Use pressure decrease of 10 mb for every 100 m of elevation Ex) What is the corrected to sea-level pressure of State College, PA if the surface pressure was measured to be 965 mb and the elevation is 350 m? -would the corrected pressure be greater or less than 965 mb? 965mb + (350m * (10mb/100m)) = 1000mb

6.7 cntd… b) -Pressure is lower at higher elevations -That’s why the air is thinner and harder to breathe in places like Denver, CO -How would a map of pressure look if left uncorrected to sea-level?

6.9a,c,d pg. 249 *NO part b a) -Identify Highs and Lows by finding relative maxima and minima of closed isobar values c) -Wind barbs show the direction the wind is coming from (you may use arrows instead) -Consider how wind flows around High and Low pressure systems d) -In general, the tighter (closer together) the isobars, the faster the wind speed -This is due to a stronger pressure gradient force

7.9a,b pg. 300 -A warmer column of air will have higher heights on a given pressure surface when compared to a colder column of air a) -Determine which location is warmest, which is coldest? -How would the temperature of each location affect the height of any given pressure level? b) -Use the same concepts from part a but instead of different locations think of different seasons

LAB #4 – DUE FRIDAY, SEPTEMBER 23rd Office Hours: Thursday 2-3 Walker 606B Email me (mzw274@psu.edu) with any questions you have about the lab! LAB #4 Assignment Summary Chapter 4: (14 a,b) (15 c) Chapter 5: (10 a,b,d) (18) Chapter 6: (2 a,b) (7 a,b) (9 a,c,d) Chapter 7: (9 a,b) There will be a review session next Tuesday night from 7:30-8:30 in 109 Walker