1. Geographical Influences on Climate Lesson
Global Precipitation Measurement Mission
Developed by the GPM Education and Public Outreach Team
NASA Goddard Space Flight Center

2. Guiding Questions
Geographic Features: What are geographic features and how do they affect temperature and precipitation?
Weather versus Climate: What are the similarities and differences between weather and climate?
Climatograms: How can you easily see climate data about a location? What analysis tools can you use to compare the climate data for different locations?
Geographical Influences on Climate: How do nearness to large bodies of water, elevation and the location of mountains affect temperature and precipitation?
This slide could be shown to students as a preview of the lesson, or used solely as a reference for the teacher.

3. Engage – Name Geographic Features
Name some geographic features you know. Can you think of any ways they might affect temperature or precipitation?
Depending on the level of your students, you may need to discuss what a geographic feature actually is (especially if you have many English Language Learners). Students may be tempted to say that man-made features count – roads, buildings, bridges, etc. You may wish to steer them toward natural features such as lakes, mountains, oceans, and so on, although the urban heat island effect could be discussed if you wish. (For more information on heat islands: The clip-art pictures will appear after the text, so you can use them as hints if your students are having trouble coming up with ideas, or as vocabulary development for English Language Learners.
Image source: Microsoft ClipArt

4. Engage – Brainstorm Effects
Geographic Feature
Effect on Weather/Climate
This is intended to be completed on a smart board of some sort – it could also be filled out on a white board or chart paper. Some features that might be discussed are mountains, lakes, oceans, rivers, hills. Students may also bring up cities - you can choose to discuss the urban heat island effect, or keep the discussion on natural geography.

5. Ash and Steam Plume, Soufriere Hills Volcano, Montserrat
Engage – Volcano!
Ash and Steam Plume, Soufriere Hills Volcano, Montserrat
THINK: Look at the NASA picture at right. Think about what geographic factors are present that might affect the weather or climate at locations A, B and C.
PAIR: Share at least one idea with your partner.
SHARE: Raise your hand if you'd like to share something you and your partner discussed.
This could be and additional engage activity, or as a more guided substitute for the brainstorming on slide 3. Students should notice that A appears to be somewhat elevated, while C is at sea level and right near the water. B is clearly being affected by the ash plume from the volcano, which may lead into a discussion of short-term versus long-term factors. (A will always be at a higher elevation, and C will always be near water, but B will not always have an ash plume over it.) A fuller discussion of weather versus climate will occur later.

6. Weather versus Climate
What is the difference between weather and climate?
weather
climate
Ideally this should be done by filling out the diagram on a Smart Board. The primary difference here is the time scale - weather is looking at the short term; whether it will rain and what the temperature will be like for the next few days. Climate is looking at the long term; data averaged over a longer period of time. It can actually be easier to make models that predict climate over the long term, even though meteorologists can't always tell us accurately if it will rain tomorrow. Both weather and climate measure temperature, precipitation, humidity, wind speed and direction, etc., but over a different time frame.

7. What do you notice about the climatogram below?
Climatograms
What do you notice about the climatogram below?
You could this climatogram of the nation’s capital, or even better, create one for your location. See the GPM Geographical Influences on Climate Teacher Guide for detailed directions.
Here is a good opportunity to check for what students remember about graphs. Things to point out:
- title
- two axes, with different scales
- units on the axes
- the key
- combination of bar graph for precipitation and line graph for temperature

8. Term to be familiar with:
Vocabulary
Term to be familiar with:
prevailing winds - which direction the wind usually blows at a particular location (referred to by the direction the wind is COMING FROM)

9. Maps of Geographic Features
What do you notice about the maps below?
These maps are similar to what students will see shortly in the exploration activity (GPM Geographical Influences on Climate – US Cities Climatograms). The shaded relief shows mountains in brown – you might point out the major ranges that are labeled. Large bodies of water (oceans, bays and large lakes) show in light blue – rivers and streams are not generally included. The arrows show prevailing wind patterns. Prevailing wind data is usually collected at airports, and can be affected by local geographic features such as river valleys, hills, etc. In general, the U.S. is in a band of westerlies, meaning the overall prevailing winds in the U.S. are from west to east (or southwest to northeast) – for this activity we will rely on this simplification, although in reality it is much more complex. For a global diagram of prevailing winds, see If you would like to look up more precise prevailing winds patters, one source (for major U.S. cities only) is The map on the right is a zoomed-in version to allow students to see more detail. In the climatograms students will be looking at, the two comparison cities that are part of each group of three will also be marked.

10. Climatograms for U.S. Cities
Look at the map and climatogram you have been given. Observe the patterns in the data, and make notes and calculations on your capture sheet about precipitation, temperature, elevation, and any land features such as oceans, lakes and mountains.
After you have examined your climatogram, you will compare yours with those of other classmates.
Distribute the GPM Geographical Influences on Climate Climatograms to students (ideally printed in color as a class set to be reused). You may need to give multiple students the same climatogram, based on your class size.
After students have time to complete the front side of the capture sheet, they will compare their data to that of other cities in a relevant grouping. Each group of three cities focuses on one key aspect of geographical influences on climate – elevation, mountains and rain shadows, coastal versus inland, and being leeward or windward of large bodies of water. See the GPM Geographical Influences on Climate Teacher Guide for questions for students to discuss about their group of locations to lead them to discover the influence each of these factors has on temperature and precipitation. A description of what it is hoped students will observe about each set of cities can also be found there. General observations for a summary of the activity are found on the slides that follow.

11. Effect on inland locations
Nearness to centers of large landmasses – Tend to have wide ranges in temperature, both between day and night, and seasonally, and tend to have dry climates.

12. Effect on coastal locations
Nearness to large bodies of water – Water has a moderating (keeping toward the middle) effect on coastal areas producing low ranges in temperature, both between day and night, and seasonally
Tend to have higher than average precipitation, especially areas on the leeward (downwind) side of the water.
NOTE: Be sure to point out that in general we mean LARGE bodies of water, not just small rivers and streams, which are not as likely to have a noticeable effect.
Image source:

13. Effect of elevation
Elevation – As elevation increases, the average yearly temperature decreases. Precipitation effects are going to depend on being on windward or leeward side of the mountain.

14. Effect of Being Near Mountains
Location relative to large mountain ranges – Windward sides of mountain ranges are cooled, while leeward (sheltered) sides are warmed.
Windward sides of mountains tend to receive higher than average precipitation, while leeward sides receive lower than average precipitation.

15. Create your own climatogram
Use the instructions to get data from NASA TRMM, weather.com, intellicast.com, wunderground.com, or other websites about a location around the world.
Follow the directions to make a climatogram using Excel.
Find your location on a map, and draw or label the features around it.
Using what you have learned about the effect of geographic features, write paragraphs describing the temperature and precipitation patterns at your location, as well as the effect of elevation, bodies of water, and mountains.
Be sure to refer to the checklists and rubric to make sure you include all the required information.
If you are running short of time, you can always have students use the GPM Geographical Influences on Climate - Climatogram Template rather than having them go through all the steps to create their own graph in Excel. As another time saver, if you would like to give students’ prepared data rather than have them seek it out themselves, see the GPM Geographical Influences on Climate Teacher Guide for data tables for various cities around the world. A good source for maps of U.S. cities on the computer is or For non-U.S. locations, try Students could digitally add a star to their location, and put it on the same page as their climatogram and descriptions. Prevailing wind direction can be tricky to find. See the Teacher Guide for a list of possible resources.

16. Extension Activities
Extension Activities

17. Rain Shadow Satellite Images
Satellite Images and the Rain Shadow Effect in the Pacific Northwest
Image sources:
(left and center)
(right)

18. Landsat 5 Image of Oregon
Within a three-hour drive across Oregon, you can visit a beach, a temperate rainforest, a mountain glacier, and the high desert. The diversity of the landscape is mostly driven by the interaction of air masses and the mountains.
This image from the Landsat 5 satellite (bands 5, 4, and 3) was acquired on October 27, The false-color view shows the high desert—bare soil and sparse vegetation appear in shades of brown and pink—and the deep green vegetation on the west side of the Cascade Mountains. The one blue spot is the glacial cap of Mount Hood.
The transition from green to brown is indicative of a rain shadow. Winds blow in from the west, carrying moisture from the Pacific Ocean. As the air moves across the landscape and up into the high elevations of the Cascade Range, air pressure decreases. The air cools and becomes unable to hold as much moisture, causing water to fall out as rain or snow. For this reason, the Cascades spend most of the year blanketed by cloud cover, and the frequent precipitation provides ample water for lush vegetation and gigantic trees.
On the eastern, leeward side of the mountains, the elevation drops, the air warms, and the air pressure increases. This effectively shuts off the rain because the air can better hold the remaining moisture. This effect is called a rain shadow and is largely responsible for the desert landscape beyond the mountains.
Image and text from:
From NASA Earth Observatory, accessed 8/6/2013,

19. Compared to a Photograph
Compared to photographs/ natural-color images from Google. (Some areas are images from satellites, but the most high-resolution images are from aerial photography.)

20. Andes Mountains
Natural-color image of the rain shadow of the Andes Mountains, 250 km southeast of La Paz, Bolivia.
Image from

21. Mahale Mountains National Park, Tanzania
This natural-color Landsat 7 image of Mahale Mountains National Park. The tall ridgeline wrings moisture from the air, but substantially more rain falls on the western (lakeside) slopes, while the eastern slopes are in a “rain shadow.” The effect of the topography on precipitation is immediately apparent in the scene, as dense, green forests exist on the western side, while browner, more arid landscapes appear on the other.
Text and image from .