Impact of Forest Thinning on Snowpack

Client Information

Name- Dr. Rand Decker; Northern Arizona University; E-mail- rd53@nau.edu

Team Name- Snowpack Engineering

Team Members and Info

Daniel Hagberg

Dlh222@nau.edu

928-451-4180

Dane Palmer

Dp252@nau.edu

480-560-7807

 

Daniel Hagberg and Dane Palmer

 

Problem Description

Ponderosa pine tree canopy intercepts snow fall effectively and, hence mature or overgrown forests with high canopy densities, effectively limit the amount of snow that reaches the forest floor. This reduces much of the precipitation that falls as snow from entering usable surface runoff during the spring melt. The purpose of this project is to build upon pre-existing data by continuing snow coursing (grid sampling snow water equivalents), at an already specified location (approximately 9 miles south of Flagstaff, AZ) in 4 different forest states: open meadow, recently thinned, thinned a while ago, and un-thinned. This project will supply another winter seasons worth of snow water equivalent (SWE) data among the different forest densities. Using the SWE data, Snowpack Engineering will gain a better understanding for how the four different forest densities retain snow over time. Additionally, experimental observations will be collected that examine the effect of wind, temperature, humidity and exposed snow surface area on the rate of snow loss due to sublimation. The rate of snow sublimation when snow is intercepted by the forest canopy will be compared to the rate of sublimation when snow reaches the forest floor.

Scope of Work

This project has been divided up into 7 different primary tasks. These tasks combine to provide an outline of the services that will be provided for this research study. The tasks are as follows:

Task 1: Project Management

Task 2: Background Research

Task 3: Experimental Design

Task 4: Data Collection

Task 5: Data Analysis

Task 6: Cost Analysis

Task 7: Recommendations

 

Task 1: Project Management

Team management will be important throughout this project. This will primarily consist of utilizing time efficiently and ensuring proficient communication within the team, as well as between the team and the client.

 

Task 2: Background Research

The purpose of this task is to identify existing research that has been performed in this field of study. The design team can use this information to educate themselves regarding what methods have been used in the past to achieve similar objectives. This information will help the team to design an effective experiment without replicating mistakes that have been made by researchers in the past.

 

Task 3: Experimental Design

The design team will run two simultaneous experiments: one studying the effects of varying forest densities on snow accumulations in each respective density, and the other examining the rate of snow sublimation due to environmental factors.

 

Task 4: Data Collection

During this task, the required data for each experiment will be gathered. The tree density experiment will involve manually taking multiple snow depth measurements and snow core samples along a traverse to obtain SWE values for each density. The tree branch mimicry experiment (aka. Birdfeeder)  will utilize a data logger to record the weight of the snow and a data logging weather station to record the weather data. Additionally the depth of snow contained by the “birdfeeder” instrument and the ground plot will be measured until all of the snow is gone.

 

Task 5: Data Analysis

The purpose of this task is to use an effective method for compiling and comparing the data that is collected from the field experiments. This will include deciding which types of graphics to be used to effectively display the gathered results. Results, such as SWE values vs. forest densities, can be compared with other similar studies performed in other regions.

Task 6: Cost Analysis

The purpose of this task is to predict the costs associated with conducting this environmental study. The predicted costs will pertain to the required equipment and the labor to implement the experiment, analyze results, and produce the design report. 

 

Task 7: Recommendations

The design team will provide recommendations to the client based on the findings, or lack thereof, from this project. Recommendations will include an optimal forest density to produce the highest water yield, how much the water yield will increase due to the implementation of the specified forest density, as well as how quickly a typical storm will sublimate entirely from the ponderosa pine tree branches. Additional recommendation may pertain to forest thinning strategies, the need for additional research, and how to modify subsequent studies.  

 

Final Products

·         Western Snow Conference Abstract

o   Snowpack Engineering will submit a 150-300 word abstract summarizing the hydrologic study and its findings.

·         Final design report

o   The final design report will provide an in depth description of the project purpose, procedure, results, conclusions and recommendations developed from the hydrologic study.

·         UGRAD Conference Poster

o    The poster will display the results, conclusions and recommendations drawn from the snow hydrology study.

o   If selected to present the results from this project at the 2012 Western Snow Conference, this poster will double as the snow conference presentation deliverable.