For the Instructor
These student materials complement the Critical Zone Science Instructor Materials. If you would like your students to have access to the student materials, we suggest you either point them at the Student Version which omits the framing pages with information designed for faculty (and this box). Or you can download these pages in several formats that you can include in your course website or local Learning Managment System. Learn more about using, modifying, and sharing InTeGrate teaching materials.Unit 4.1: Energy Budgets
Introduction
The purpose of this unit is to explore, compare, contrast and calculate energy fluxes from different CZO field sites to better appreciate the critical differences in the driving radiative forces affecting each site. This module will help you complete your semester-long project by introducing you to critical baseline data collection and data bases related to energy budgets.
The primary data set for this activity is the CZO tower network of a dozen met/flux towers spanning six different biomes/sites. Each site has a slightly different data format but it is easily manipulated in a spreadsheet. The lesson is divided into the following engaging activities. In this unit, you will:
- use water and energy cycle diagrams to discuss how water and energy are partitioned at the watershed scale
- learn about the instrumentation used to collect water and energy flux data
- examine radiative forcings collected from various CZO sites to compare various climatic and site-specific influences
- explore and visualize energy flux data from the CZO database
- calculate a measure of Effective Energy and Mass Transfer (EEMT) related to the potential for Critical Zone evolution
- use CZO micro meteorological data to calculate reference evaporation at a site of choice.
Unit 4.1: Energy Budgets
Part 1 - Energy Flux
Pre-class- Read Rasmussen, et.al, 2011, An open system framework for integrating critical zone structure and function , Biogeochem, 102:15-29, DOI 10.1007/s10533-010-9476-8 (link may require Springer on-line subscription).
In-class
Introduction to Water and Energy Budgets & Fluxes
- The following lecture notes will introduce you to water and energy budgets and fluxes.
- Standard Lecture: Introduction to Water and Energy Budgets & Fluxes (24 slides, ~35 min)
- Student Lecture Notes: Introduction to Water/Energy Budgets & Fluxes - Printable (6/pg) Student Note Set (Acrobat (PDF) 754kB Feb23 17)
Energy Flux Graphing Activity
- In this activity, you will explore CZO Met/Flux Field Sites & Database.These slides will introduce you to the original six Critical Zone Observatories to give you an idea of the physiologic setting. Working with the CZO Met/Flux Database: Energy Flux Graphing Activity - The ultimate goal is to get you actually working with typically archived energy flux data, first by graphing it and then by using it to calculate something called reference evaporation.
- Notes: CZO Field Sites and Data- Printable (6/pg) Student Note Set (Acrobat (PDF) 2.4MB Aug26 24).
- Handout: CZO field site Available Database Tables (PDF) (Acrobat (PDF) 93kB Oct14 13).
- Worksheet: Energy Flux Graphing Activity (PDF) (Acrobat (PDF) 89kB Mar17 16).
- Look for a different data set and make 2 plots with at least 2 variables/plot of meteorological variables (such as TA or VPD) and energy flux variables such as (Rn, H or LE) versus Calendar or Julian date. Once you have the basic plot, make sure you make it readable (titles, etc).
- Set 1: Annual period - at least 2 meteorologic parameters and 2 energy parameters.
- Set 2: Ten-day period - at least 2 meteorologic parameters and 2 energy parameters.
- If you are having trouble downloading from the CZO data archive, try using the following two files:
- Getting Started Dataset 1: WY_2010_Lower_Prov_Met_daily from Sierra CZO - 365 lines (Comma Separated Values 56kB Jul4 16).
- Getting Started Dataset 2: Tower Vcm_2010_gapfilled_14day@30min from Jemez CZO - 721 lines (Comma Separated Values 56kB Jul15 24).
Part 2 - Annual Energy Balance
Pre-class- Read Brown, P.; Standardized Reference Evapotranspiration, AZ Coop.Extension, 2005, 12 p. and examine reference ET Formula Sheet (Acrobat (PDF) 146kB Oct27 13) (from Brown, 2005).
In-class
Review of homework
- You will start with a review of any issues and the homework associated with the energy flux activity that was started and assigned last period.
Annual Energy Balance Graphs Activity
- You will examine the six graphs in the Handout (below) for patterns and speculate as to what controls the timing and magnitude of fluxes.
- Student Worksheet: Energy Flux Discovery Activity (Acrobat (PDF) 287kB Apr13 17) (PDF).
- Handout: Set of six Energy Flux Discovery Graphs (Acrobat (PDF) 212kB Oct14 13).
- Student Handout: Set of 6 Energy Flux Discovery Graphs (Acrobat (PDF) 212kB Oct14 13) (PDF).
Additional Resources
Sources of Data
- Critical Zone Observatory National Database, http://criticalzone.org/national/data/
Background References
- Sustainability-Water: Sierra Nevada Snow Pack & Snow Melt (with Dr. Martha Conklin!), NBC Learn, air date 6/26/13.
- Allen, R.; ASCE-EWRI Standardization of Reference Evapotranspiration, ID Ag. Experiment Sta., http://www.kimberly.uidaho.edu/water/asceewri/appendix.pdf
- Allen, Pereira, Raes, Smith; Crop evapotranspiration - Guidelines for computing crop water requirements - FAO Irrigation and drainage paper 56, http://www.fao.org/docrep/x0490e/x0490e00.htm#Contents
- Excellent slides on global climate system: http://www.iac.ethz.ch/edu/courses/bachelor/vertiefung/climate_systems
Other Useful Information
- List of CZO tower sites with annual data Tower site basic info (Acrobat (PDF) 48kB Jul6 13)
- Column index for CZO tower data files - useful for graphing Tower column index (Acrobat (PDF) 46kB Jul6 13)
- Yearly index of CZO Met site coverage Met site yearly coverage (Acrobat (PDF) 75kB Jul6 13)