Atm Ocn 100 1st Edition Lecture 5 Outline of Last Lecture I Website of the day Notes II Surface Pressure III Humidity IV Vertical Structure of Atmospheric Temperature Outline of Current Lecture II New Homework Assignment for Friday III Website of the Day IV Vertical Structure of Temperature in Atmosphere V Heat vs Temperature VI Heat VII Energy and Temperature VIII Energy Transfer IX Primary Observed Weather Variables X Conventional Observations XI Standard Station Models Current Lecture Homework Skip every other point to have less clutter in graph for Chapter 2 homework assignment But plot every temperature point on that graph Rawinsonde Launch Friday September 19th a Wednesday September 17 Bill Olson of the Space Sciences and Engineering Center b Supplementary Homework Assignment a The temperature dew point depression and winds that will be measured at 500 mb pressure or relative humidity just want the moisture wind in knots b The pressure and magnitude of the strongest winds at any height the launch based on model predictions on the web jet stream of that day that will be over us look through all weather maps at different levels and find out what the strongest wind is predicted to be 1 Go to a web page showing GFS or NAM predictions for Friday based on the most recent forecast 2 You can use either NCEP http mag ncep noaa gov website or AOS web site http www aos wisc edu weather wx models Models htm NCEP is probably the best web site to use for this Purpose is to help us become familiar with reading these prediction maps and relating what they predict to what a rawinsonde measures 3 Look from a time close to class time when balloon will be launched and determine as best we can from the contours the requested quantities from above email them to Stephen by 8 am Friday September 19th Class will meet outside on Friday For our homework assignment Friday is 4 and a half days away which is 108 hours away So what time do we want In UTC 11 Madison time means 16 UTC 15 UTC is pretty close to this at 500 mb The Site we should use Model Guidance Go to Namer North American Then GFS 500 Temp ht and 105 hours Temperature for Friday predictions 11 maybe even 11 5 close to 12 isotherm Winds are out of northwest varies a little bit from one place to another The winds are in middle out of the northwest and it looks like 22 knots something like that Then we can switch to the relative humidity map 105 again for hours The light green is the relative humidity Scale looks to be 75 Then we want to look at the maximum wind at all the heights To do this we need to find the strongest wind It looks to be about 65 knots with the northwest wind at 200 mb We should also look at 250 to determine strongest wind To do this look at the middle of the weather map and find the jet stream This will convey in knots what the strongest wind is Why are we doing this To learn more about how to read weather maps and be able to forecast the weather in the future Website of the day http tropic ssec wisc edu Tropical Cyclone over Baja California From the images we can see the eye of hurricane Edouard There are winds underneath swirling in which is basically a picture of the cyclone We as a class are looking at the eye of the hurricane There are shallow cumulous clouds in the eye The wind strength in the eye is about 80 90 knots On this website we can see the track of the storm as it forecasts Most hurricanes don t actually make landfall Outer part of the picture we are looking at through this website is rotating clockwise If we are looking at individual clouds on top we may think that they are rotating in different directions But the storm itself in the lower parts are actually rotating counter clockwise at lower levels Back to lecture Last time we ended with vertical structure of temperature in the atmosphere From this graph we are looking at on the lecture PowerPoint slides we can see that the atmosphere is divided into several spheres the lowest part above our main sphere which is the troposphere is the tropopause Deep cumulous clouds or thunderstorms clouds can grow vertically up into the tropopause The tropopause defines vertical extent to what can take place Thunderstorms define the overture of air Tropical cyclones don t overturn as deep turbulence in the air The jetstream level is close to level of the tropopause The tropopause is a boundary between the Troposphere and the Stratosphere The tropopause can be thought of as a lid on the Earth s weather because it prevents vertical air currents such as ones from storms from moving into the Stratosphere The tropopause slopes downward from the tropics to the poles In the tropics the tropopause occurs at a higher altitude than while at the polar latitudes Because of this tropical storms grow to greater heights than storms in Polar Regions The tropopause has folds in it which is one way that air in Stratosphere mixes with air in the troposphere We will learn more about this later The tropopause is normally close to the level of jet stream Jet stream that occurs in the atmosphere is the result of the integrated effect of temperature gradient with height Thermal gradient between tropics and poles means that there is an increase of temperature with height When thermal contrast stops which as at the top of the tropopause wind is at its maximum Which is why we can measure here for the Jetstream Jet streams occur where height of the thermal contrast is the greatest which is the tropopause As we get into the stratosphere we know that temperature increases with height Sun as it heats and moistens can affect causes unstable overturning turbulence in atmosphere In the stratosphere temperature increases with height The reason for this is because there is ozone in this layer that absorbs ultraviolent radiation from the sun which then therefore warms the atmosphere up Dirt or dust that gets into the stratosphere has a hard getting out The reason for this is that the stratosphere is very stable air just sits up there Heat vs Temperature Temperature is proportional to the heat per unit mass of a substance Proportionality constant is called the heat capacity of a substance The higher the heat capacity the more thermal energy that is stored per change of temperature Heat is the amount of thermal energy transferred from one place to another during a thermodynamic process What is the difference Warm temperature means there is a lot of heat Heat is a measurement of heat capacity of a substance
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