Meteorology 302.01, Spring
2004
Class Notes for February 23, 2004
Trevor Harrison
Jacki Dick
Assignments
Midterm #1, Monday, 1 March (Discussed Friday 27 February)
Edit: Midterm postponed until Wednesday, 3 March.
No new
reading
Housekeeping
- Received corrected Homework #1
(Solutions will always be posted on class website after it is returned)
The class average was 86/100 with no letter grades assigned. You did well if you scored 80 or above on the homework. If there is a problem with the grade, points can be gained by convincing Professor Monteverdi.
Upcoming Weather Pattern
We looked at the Hydrometeorological Prediction Center website. This organization predicts floods. A major storm is expected mid-week, most of it Tuesday night and Wednesday. We also looked at the Storm Prediction Center’s website’s Convective Outlook for Wednesday.
Radar Recap
Remember, radar allows us to see exactly where precipitation is. From this information, we can logically infer clouds are present where precipitation is. Colors represent the amount and intensity of rainfall or precipitation.
Next, we looked at the NOAA website’s current radar reflectivity from radar of the US for examples of storms over Alabama and Texas. The circular pattern shown is attributed to the radar’s circular rotation. Looping of these radar images can be used to forecast how fast a storm will move into a given area.
If hail is present, it will be indicated with an arrow labeled hail.
Key Terms:
Radar - Device that sends a signal that spins quickly making a circle encompassing a radius of 100 miles.
Radar Chart - Shows location of rainfall when chart is drawn.
Front
Recap
Remember, a front is a boundary between warmer and colder air. Heretofore, we have only studied warm and cold fronts in the continental US. However, two kinds of fronts dictate most weather around our violent planet. The polar front (shown in blue) is the boundary separating cold air masses from warm air masses and it extends all around the world. This is found at both the North and South Poles. Where the warm tropical air masses (shown in red) meet the polar fronts is illustrated on the map in white. To demonstrate this further, we looked at the Global Temperatures at the 700 mb Level website. This diagram illustrates common sense – cold air is found at the poles and warm air is found in the tropical/equatorial region. Still or looped images are available at that site. These fronts are associated with significant bad weather.
Construct Your Own Weather Map
Another website useful for teachers (as well as meteorology students) is the Construct Your Own Weather Map. This link can be found on the main page under “Frequently Used Graphics”. (If you have a slow internet connection, allow a few minutes for all the graphics/maps to load.)
We will not deal with all of the available options on this map this semester, but will be responsible for 5 or 6 of them. By clicking on the appropriate box, the map will plot what was requested. If you click on the underlined word next to the boxes on this page, a brief explanation is shown.
We covered “MSLP” found under the “Low, mid, high overlays” heading. “MSLP” is short for sea level pressures. Therefore, current isobars at sea level will be drawn by computer (a surface weather map).
Also discussed was the “10m BKNT”. This shows wind barbs without the accompanying weather station information. Unlike the surface plot maps we have used previously, the “10m BKNT” shows wind speed at 50 mile intervals as opposed to 200 mile intervals. The winds on the map follow the pressure rules of thumb covered in previous classes.
Next we covered the top two options on the map: “2m T” and “2m Td”.
“2m T” shows the current temperatures 2 meters above the ground in isotherms. Isotherms are lines that connect points that have the same temperature. The isotherms are drawn at 10 degree intervals. The areas of equal temperatures are colored the same. With the “2m T” box still checked, we superimposed the wind (“10m BKNT”) overlay to see where warmer air and colder air meet, forming a front.
“2m Td” shows the current dew point temperatures 2 meters above the ground. Because this is used primarily for thunderstorms, severe thunderstorms, and tornados, dew point temperatures less than 44F are not plotted. In the future we will learn that the higher the dew point temperature, the more liable thunderstorms are to occur.
Dew Point Temperature
Areas with higher dew points, and higher water pressure are more prone to experience thunderstorms. Naturally, the areas around such places such as the Gulf of Mexico experience more thunderstorms due to the amount of water vapor.
Scientific Method
The scientific method is a blue print that all scientists use to study (and solve) problems in the natural world. This method is used in nearly every field and or discipline. There are five major steps in the Scientific Method (assigned):
1. Make a set of observations - (i.e.) annual precipitation values across and along a mountain range.
2. Define a problem evident from an examination of the observations
3. Formulate a hypothesis to explain the problem using proven principles
4. Test the hypothesis by experimentation
5a. Derive a theory based upon successful experimentation
5b. Modify hypothesis or redefine problem if experimentation does NOT bear out hypothesis.
The main goal of the scientific method is to create a theory thereby making predictions possible. However, the whole procedure is prone to mistakes, and therefore, it is set up to find the mistakes. It is also easy to circumvent the scientific method, creating controversies and a disservice to science.
Next we reviewed the procedure pyramid (found in our book designed) to show how the scientific method works.
Key term: Theory - a proven hypothesis.
Keep in mind, in the field of statistics (working with numbers allowing inferences), there are no stereotypes or human bias.
Next we reviewed the foundations of the scientific method:
· The first step/foundation is based on determinism: for every effect there is a cause (pg. 38- Zebrowsky).
· The second step/foundation states that if several conflicting explanations exist for the same thing, the best explanation is the one that has the fewest assumptions in it. This is also known as K.I.S.S. – Keep It Simple Stupid.
Next time…. Fringe science - “If you don’t like it, prove I am wrong.”
