Lesson Plans

Using Precipitation and Vegetation to Study Climate Zones

Monthly Normalized Difference Vegetation Index’

Purpose

Scientists are interested in learning how the vegetation (collection of plants) of an area can be used to study Earth's climate. In this lesson, students observe average values of global precipitation and vegetation over the course of one month using NASA visualizations created from satellite data. Students investigate possible relationships between the vegetation and precipitation.

Learning Objectives

  • The students observe and analyze monthly global precipitation and vegetation values from 2012.

  • The students make inferences about the role that geographic position has in the distribution of precipitation and vegetation at a global scale.

  • The students analyze locations (of their choice) for possible patterns and relationships between precipitation and vegetation.

NASA Phenomenon Connection

 

Scientists are interested in learning how the vegetation of an area can be used to study Earth's climate. Climates can be broadly classified using seasonal and yearly atmospheric conditions which in turn affect global distributions of vegetation and soils. NASA scientists use data from multiple satellites to analyze the relationship of precipitation with vegetation. In this My NASA Data Lesson, Using Precipitation and Vegetation to Study Climate Zones, students observe different visualizations to identify patterns precipitation and vegetation data as they change over time and space.

Essential Questions

  1. In what ways is the Biosphere connected to the Hydrosphere?

  2. How does the Geosphere affect global patterns of precipitation and vegetation?

  3. What factors affect the amount of precipitation that a region has? How does precipitation change over time?

Cross-Curricular Connections

National Geography Standards:

-How to use maps and other geographic representations, tools, and technologies to acquire, process, and report information from a spatial perspective.

STEM Career Connections

  • Soil and Plant Scientists – Analyze biological samples, classify organisms based on their characteristics or behavior, conduct research of processes in natural or industrial ecosystems, and research crop management methods.

  • Atmospheric and Space Scientists – Investigate weather and climate-related phenomena to prepare weather and climate-related phenomena to prepare weather reports and forecasts for the public

  • Environmental Planners – Analyze and minimize impacts associated with development projects in urban and regional environments.

  • Cartographers and Photogrammetrists – Collect, analyze, and interpret geographic data in creation of maps

Materials Required

Per Student:

  • Using Precipitation and Vegetation to Study Climate Zones Datasheet

Per Group:

  • Copy of Student Pages:

    • Monthly Precipitation

    • Monthly Normalized Difference Vegetation Index

Prerequisites Student Knowledge

  • Seasonal changes related to weather

  • Names of continents

  • Latitude/Longitude

  • Basic ability to read a map

Student Misconception

  • “The intensity of sunlight at a place does not change from day to day during the year (AAAS Project 2061, n.d.).”

  • “Thermal energy cannot be transferred between air and water (AAAS Project 2061, n.d.).”

                                                                                                              
                                                                          -Credit: AAAS Science Links

Procedure

Part 1: Engage the Learner

  1. Engage prior knowledge by reviewing the concepts of weather vs climate to students (2 minutes)

  2. Scientists are interested in learning how the vegetation of an area can be used to study Earth's climate. Today we are going to make observations about the collection of plants (vegetation) in a region and precipitation as climate indicators.  

  3. Tell students that they are going to observe Monthly images collected by a NASA satellite and share the Monthly Precipitation (GPCP) image first with the class.Precipitation Global Map

  4. Distribute the Student Datasheet.  Review the key topics below for Part 1:  Observe Precipitation & Vegetation Visualizations, while also following along with Teacher Key of Student Datasheet.  

    1. Review the legend of this image.   These values are in (mm/day).

    2. What does the dark brown (or white on greyscale)  represent? Drier conditions

    3. What does the dark blue (black on greyscale) represent? More precipitation

    4. What month does this represent? May 2012

    5. Look at the Pacific Ocean. Notice the unique pattern of a streak of precipitation in a zone of dryness. Why is that? That is where the equator is. This is where we find a lot of rainforests because of the convection cells around earth from the level of radiation from the Sun.

    6. What are climate conditions we might expect in May? Accept a broad spectrum of answers but emphasis how it depends on where you are on Earth. NDVI Values

  5. Healthy and dense vegetation absorbs most visible light from the Sun and reflects near-infrared light. Unhealthy or little vegetation reflects more visible light from the Sun and less near-infrared light. Because of this, satellites can measure the amount of reflected visible and near-infrared light to determine the number of plants on the surface of the Earth. Normalized Difference Vegetation Index, or NDVI, is measured from both types of light. Scientists use the word “index” to mean a measurement of something, so NDVI is a measurement of plants based on the difference between two types of light.

  6. Now, review the ‘Monthly Normalized Difference Vegetation Index’ (taken from May 2012). Describe that scientists use the Multi-Angle Imaging SpectroRadiometer (MISR) on the Terra satellite to record the type of light, ultraviolet and infrared, reflected from the foliage of the various plants on Earth. Scientists then mathematically process the data, and the result is known as the Normalized Difference Vegetation Index or NDVI. Explain to students that this image represents the NDVI; it is a measure of how much plant life is on the surface of the Earth. It is averaged over the month.

  7. Review the legend of this image.  

    Monthly Normalized Difference Vegetation Index’ (taken from May 2012)
    Monthly Normalized Difference Vegetation Index’ (taken from May 2012)

     

  8. What does the bright green (or black on grayscale)  represent? High values (0.6-0.9) indicate temperate and dense tropical forests.

  9. What does the white (light gray on grayscale) represent? Low values of NDVI (0-0.1) indicate barren or snow-covered land. Middle values (0.2-0.5) indicate shrubs and grasslands.

  10. What month does this represent? May 2012

  11. What are the global patterns that these images usually show? Around the equator? Between the poles and the equator?

    1. The equator has high temperatures and precipitations year round so have vegetation levels throughout the year.

    2. Between the poles and equator, there are rises and falls of vegetation greenness with seasonal changes.

 

Part 2: Compare visualizations

  1. Now compare the two images and critique these.

    1. What is one similarity and one difference between how the data look?
      1. Similarity: They have a higher concentration point in the same area
      2. Differences: It is limited to just the continents.
  2. Locate an area that has much precipitation but little vegetation.

    1. Qualitative Observations:

    2. Quantitative Observations:

  3. Find an area where little precipitation has occurred, yet there is still vegetation

    1. Qualitative Observations:
    2. Quantitative Observations:

Part 3:  Investigate Relationships & Patterns

  1. Students investigate an area that has a high level of precipitation.

    1. What is the vegetation level?

    2. What is the latitude/longitude?

    3. What is the NDVI value?

    4. How may these areas be related?  

      1. What additional datasets would you like to review or would be a good match to compare with NDVI?

  2. Students investigate an area that has a low level of precipitation.

    1. What is the level of vegetation?

    2. What is the latitude/longitude?

    3. What is the NDVI value?

    4. How may these areas be related?  

    5. What additional datasets would you like to review or would be a good match to compare with NDVI?

  3. State a claim based on evidence.

    1. The claim that when ___________, then __________ (happens).

  4. Bring the class together to share what they found.