Draw the frontal boundary in the figure below: In this exercise, you will be drawing isobars on a weather chart. Here is an example: In addition to isobars this map includes the centers of high and low pressure areas, the position of warm, cold and stationary fronts, and precipitation. Note the key at the top of the first one: Next, show them a different weather map, one that shows isobars. You will want to have a few extra maps on hand in case students need to start over. In the figure below, an isotherm line of constant temperature is constructed through 80°F. .
What time of the year was this captured? On the following weather map, draw isotherms at 45°, 55° and 65° F. They finish the lab with a very basic analysis and a few Regents-based question before ending for the day! Again, ask your students what they notice in the image. The embedded notes in the connected Word document above indicate that I give students the first definition and then ask them to come up with the other two, but in execution, I found that by this point the students could more or less define all three terms with little assistance. To estimate these points, you would find pairs of adjacent stations close to 50°: one station above 50° and the other below 50°. Have students replicate the isotherm on their own laboratory sheets. These are called isobars, lines of equal air pressure.
Hand out the and have your students with a partner optional to complete the exercise. In a simple interpolation scheme we might decide that 1012 Mb is exactly between 1010. Have them pay attention to the lines and ask what they might represent. This should be a review question for them if you have previously taught a lesson on the relationship between air pressure and altitude like the lesson found. What are the boundaries between the colors? Using the table and the weather station model above, complete the following: Weather maps become most useful when their information is analyzed in some fashion.
Show them one last image, shown below, projected onto the board that includes only the air pressure values and not the lines. Once student groups are finished with the isotherm map, they're allowed to immediately transition into the more challenging map on the last page of the attached resource. In particular, I found most students didn't make a 70 degree isotherm, even though they noticed a 71 degree point on the map. For a printer friendly version of this lab, click. We start at the top of the resource, where I have students read out the rules one-by-one.
In the video below, two of my students demonstrate their understanding of the interaction of these Earth systems at the conclusion of the lesson. The following types of air masses result: Maritime equatorial mE Maritime tropical mT Maritime polar mP Continental tropical cT Continental polar cP Continental arctic cA Note: Continental equatorial and Maritime arctic air masses are rarely found. I make sure to spend time at the end of this lesson to insure that my students are understanding how to interpret and make sense of this data, in particular, the relationship between air pressure, temperature, fronts and precipitation as we will use these connections when making weather forecasts in a future lesson in this unit. Anyway, once that transition is complete, I ask that they begin with the isotherm map on the second page of the resource, both following the rules in the previous section and the directions on the first page of the. Before the next section starts, I have students transition into the laboratory groups. You should note that the attached resource is the same as the in the bottom Closing section, but should definitely be started if students have time available. How would this map look at different times of the year? Background: The purpose of this lab is to illustrate the construction and use of weather maps and to help you identify air masses, fronts, and mid-latitude cyclones on weather maps.
What is the unit of measurement? Based on the source regions shown by the ovals, use the appropriate two-letter code to indicate each air mass type. Nite, you can also have them identify the centers of high and low pressure. In this lesson students will learn how isolines are used in the creation of weather maps to show areas of similar temperature isotherms and areas with similar barometric pressure isobars. Ask them how the values would change if the measurements were taken at higher and yet higher altitudes. Once that time is reached, no lab or computer work, if they are out should continue.
As structured, and visual, as this activity is presented, I have found that often students need additional instruction, so be prepared to go back over the previous exercises. It is a good idea to have taught this lesson first. What do the colors represent? In the last few minutes of class, I definitely want to have the room ready for either my next period, or an alternate class that might be using the room I share a room with another science teacher, which makes clean up all the more important at the end of the period. Students are also asked to make sure they have the associated the same document in the previous section to complete if their group did not yet get the chance to do so. Complete the analysis in the figure above by constructing isotherms at 70°F and at 75°F. The final step of the process involves important vocabulary words, which I ask the students for help in defining. For example: if you wanted to draw a 50° isotherm, you need to locate a number of places on the chart at 50°.
Briefly describe how you determine the points used to construct an isotherm. This creates a pretty fair representation of larger lab groups in my classroom, and, like most things, this process is timed. This section is intended to be very brief, but it is arguably the most critical part of the entire lesson, as failure to adhere to some of the basic rules that they learn in this section will mean completely incorrect isoline map construction techniques. Before proceeding please refer to my lesson on for the content listed above. As a note, there are no special materials or equipment needed for this lab. Once the class is completed with the activity, ask them how air masses affect the presence of isotherms and isobars. One means of analysis is to highlight the patterns of specific variables.
Is there a key we can create? Draw isobars at 1004 mb, 1008 mb, 1012 mb b. Based on your knowledge of isotherms, answer the following questions: 4. I inform them that as the rules indicate, you should go up in the same interval in this case, the interval is 10 degrees until you have no values that reach the higher interval again, I stop at 70 because there are no points on the isotherm map that are higher than 80 degrees. We then place a 10 in front, and the barometric pressure is actually 1012. Here is an example: Ask your students to describe the patterns they see in the image.
Air masses often migrate from their source regions and affect mid-latitude weather. Being that each weather station collects data for as many as eighteen weather characteristics, a method of symbolization must be used to include all this information on a single weather map. I'm leaving the website in the resource because it may be helpful for you, or you may as I do have some really advanced groups that work well together and have extra time. As of now, two of my classes have done this entire transition I stop the timer when everyone is seated in six seconds! One idea to help your class get started is to project the map on the board and walk them through drawing in the isotherm and isobar lines. Additionally, as will be noted in the next section, anything not done is meant and intended to be completed for homework at home.