Watershed Dynamics Colleen Buzby David Smith Aida A wad Awad

Transcription

1 Watershed Dynamics Colleen Buzby David Smith Aida Awad

2 Project Description: Where does your water come from? Do you always have enough or is the supply limited where you live? What factors affect the quantity of the water where you live? The GLOBE Watershed Dynamics Project offers students the opportunity to conduct scientific investigations on watershed behavior on local, regional, and national scales, using real-time and archival data from the large-scale scientific observatory being constructed by the Consortium of Universities for Advancement of Hydrologic Science (CUAHSI Of particular relevance to this project, CUAHSI is developing a Hydrologic Information System (HIS) that combines easy access to geographic data and hydrologic data, including USGS stream gages, stream flow and land cover data. In the Watershed Dynamics curriculum, students use My World GIS TM ( to access this data and analyze it. The first module has students study the water cycle by comparing rates of precipitation, evaporation, and surface runoff to see how they measure up to one another in different parts of the country. In the second module, students look at land use data and stream gage data to see if they can find a relationship between surface type and stream flow. Each module is approximately days long. These lessons and GIS tools will enable GLOBE students to investigate their own watershed in order to understand the flow of water through the watershed, how human activities within the watershed have been shaped by its hydrology, and how human land use is impacting the hydrology of the watershed.

3 Module 1 1. Water Availability 2. Watershed Investigations When does precipitation come? Where does it go? What is a watershed? How do humans impact the watershed? As land cover changes g over time, how does streamflow respond?

4 St d t M W ld GIS t l k t NARR (N th A i R i l R l i ) Students use My World GIS to look at NARR (North American Regional Reanalysis) precipitation data and analyze which areas of the country have the most rainfall. Red represents lowest rainfall totals while blue represents the highest.

5 Using the Analyze tool, students can select the values they are interested in studying. In this image, students select the very high precipitation data. This is where there is greater than or equal to 125 centimeters of rain. Students also make selections of high, low, and very low precipitation. You can see the very high precipitation selection below.

6 Students look at evaporation and surface runoff to see how they compare to the precipitation data. They create a map table of the data to look at how the different parts of the water budget are related to one another. They complete a data table for annual precipitation, evaporation, and surface runoff data across the country. City Ann ual Ann ual Ann ual Sur face Prec ipitation, cm Evaporation, cm Runoff, cm Student Location Denver Seattle Orlando Phoenix City of their choice City of their choice

7 Students look at how precipitation and surface runoff relate to one another across the seasons by studying map tables with different types of data and analyzing the patterns.

8 Curriculum in Action Here students from Aida Awad s classroom at Maine East High School work together to interpret the precipitation data.

9 Module 2 1. Water Availability 2. Watershed Investigations When does precipitation come? Where does it go? What is a watershed? How do humans impact the watershed? As land cover changes g over time, how does streamflow respond?

10 Lake Michigan Chicago Students launch My World to do a case study on a watershed near Chicago, Illinois. The project file contains National Land Cover Data, which h is re-classified as Developed, Agriculture, and Undisturbed to make the data accessible to students. 10 km Students analyze the National Land Cover Data from 1992 and 2001 to measure the change in land cover over time. From this they will investigate whether land cover has an impact on streamflow in the Des Plaines watershed.

11 To visualize the land cover change over time, students create a map table of land cover in 1992 and land cover in To analyze the data, they find the area of each classification and build a bar chart of the change between 1992 and 2001.

12 To find a change in streamflow, students need to access discharge data. Students use My World to access NWIS (National Water Information System) to add stream gage locations to the map. My World accesses NWIS live via an open internet connection and creates a new layer. Students use the Get Info tool to find a stream gage along Students use the Get Info tool to find a stream gage along the Des Plaines River. This is the gage they will use to study time series data on discharge.

13 To see the time series data, students click the Time Series for Layer tool and open a new window which displays the hydrograph. Students collect statistical data from this graph and look for patterns. Using the NWIS gage for geographic information, students access the CUAHSI HIS (Hydrologic Information System) to import a time series layer containing average daily discharge for the stream gage for the same years as the National Land Cover Data.

14 In the Time Series for Layer window, students can extract the data they are most interested t in. They can select a specific event to find statistical data on it. Students perform this extraction twice, once for 1992 and once for They identify two events, one in 1992 and one in 2001, with similar average discharges. From this they make evaluate whether there was a change in the pattern of streamflow between 1992 and 2001.

15 When students complete the case study, they write an action statement about what the local government should do based on what they learned. Local governments are very interested t in determining i the environmental consequences of rapid land cover change. Write a proposal to your local government describing what course of action should be taken to respond to changes in land cover. Think about the ways land cover in your area is changing. In your proposal, include information about the potential changes to streamflow and how it might affect the people in the area. Be sure to include specific environmental conditions that t exist in your local area. After this, students can access National Map Seamless Server and download the, p National Land Cover Data for their own area and recreate the the investigation.

16 Implementation Feedback Nearly all teachers agreed that the unit helped student learning, and that the August training adequately prepared them (90%) The teachers agreed that t the unit activities iti were well aligned with: standards and curricular frameworks (100%) state and district assessments (100%) Most teachers said the majority of their students paid close attention during the unit (80%) were interested in working on the unit (75%) Most of the teachers (70%) would recommend the unit, as is, to a colleague

17 70% 60% 50% 40% 30% 20% 10% 0% Students Responses to Daily Activities (How often dd did you feel ) successful at activities really concentrating skilled bored Most of the Time or Always were interesting activities weree fun mportant future eager to learn more portant for NOW excited about activities activities were too easy frustrated Sometimes Never or Seldom activities learning i learning im activities were too difficult

18 Gains in Student Learning 60% Score gain Pre-test scores averaged 37% Post-test scores averaged 43% significant 6% gain t-statistic = 7.02, p<.0001 effect size = item assessment Knowledge of watersheds and interpretation of hydrographs Reliability levels of 0.53 (pretest) and 0.71 (posttest), using Cronbach s Alpha 50% 40% 30% 20% Pre Post Item 7: On which date did the discharge rate on the Millstone River increase the most in one day?

19 Students Thoughts About College 100% 90% 80% 70% Pretest: Interested or Very Interested 60% 50% Posttest: Interest Decreased Posttest: Interest Increased 40% 30% 20% 10% 0% Graduating from high school Going to college Scienc nce as a major Engineering as a major Computer studie dies as a major Mathematic atics as a major

20 These two modules are also being adapted to a web-based GIS tool written in the Flex API which accesses an ArcServer. Benefits: Teachers would not have to deal with installation ti and licensing i of a desktop software. They won t need disk space for large data sets.