Project-Based Learning, Surface Energy Balance, and Establishment of a New Undergraduate Weather Station

Journal of Geoscience Education, May 2006 by Baker, R David

ABSTRACT

Through collaborative and individual projects in two upper level courses, undergraduate students established a new surface environmental observation station (Austin College Weather Station). In addition to standard meteorological observations, the Austin College Weather Station detects radiation and soil measurements. These additional measurements are used to calculate the local surface energy balance, an important indicator of local climate system interactions.

The weather station projects provided excellent opportunities for students to participate actively in the scientific process. The first phase involved establishment of the weather station. In this semester-long collaborative project, students engaged in all aspects of scientific field research, including planning, testing, implementation, data collection, analysis, and evaluation. They became experts on two weather station instruments. The second phase involved calibration and validation of the Austin College Weather Station. These 7-week individual projects required student research proposals, research papers, and peer review.

Student learning outcomes included both scientific content and scientific process. Many innovative assessment tools were utilized, including proposal writing, peer review, group meetings, research presentations, research papers, and a faculty review panel. These courses both received strong marks from students for promoting critical thinking and teaching effectiveness. Perhaps most importantly, students had fun participating in these research projects with real-world applications.

INTRODUCTION

Finding authentic ways to engage students actively in the learning process poses one of the greatest challenges in Earth system science education. Traditional lectures and laboratory exercises provide necessary foundations of knowledge, but they often limit students' participation in the scientific process. Indeed, the National Science Education Standards identify inquiry-based learning as the preferred method for teaching science. With inquiry-based learning, students engage in many of the same activities and thinking processes as scientists (National Research Council, 2(300).

Project-based learning provides an ideal conduit for such inquiry. Student projects shift the emphasis away from teacher-centered instruction to student-centered inquiry. Depending on the scope of the course, project duration can range from a few days to a semester or more. With project-based learning, students may conduct background research, collect data, compare observations with theory, and draw conclusions based on their research. Students often learn from their mistakes and must modify their approaches to obtain better results. They may collaborate with peers and build on strengths provided by group members. Because of the interdisciplinary nature of project-based learning, projects have been successfully implemented in many geoscience courses (e.g., Woltemade and Stanitski-Martin, 2002; George and Becker, 2003).

This paper describes project-based student research activities that established and calibrated a new undergraduate environmental observation station, the Austin College Weather Station (ACWX). The Austin College Weather Station project consisted of two major phases: 1) a semester-long collaborative course project in spring 2001 to establish the weather station, and 2) individual seven-week course projects in fall 2001 to calibrate and validate ACWX measurements. Although this environmental station measures both atmospheric and soil quantities, we adopted the name "weather station" due to widespread public understanding of the term. From ACWX atmospheric and soil measurements, the local surface energy balance can be calculated. Although surface energy balance provides important clues about land-atmosphere interaction ana local climate conditions, these difficult measurements are not recorded at typical weather stations. Austin College is the only liberal arts college in the United States to make such measurements.

Investigation of surface energy balance provides an easy pathway for exploring Earth as an interacting system. In simple terms, systems thinking involves reservoirs and exchanges among these reservoirs. For the Earth system, these reservoirs include the atmosphere, geosphere, hydrosphere, and biosphere. Fluxes among these reservoirs occur through energy and/or mass exchange. Surface energy balance studies primarily explore the exchange of energy between the atmosphere and geosphere. The presence of water (hydrosphere) and vegetation (biosphere) also can dramatically influence this energy exchange. Thus, surface energy balance involves interactions among all four "spheres" of the Earth system. Since the Austin College Weather Station measures the surface energy balance, the weather station projects provided unique opportunities for students to learn Earth system science.

SURFACE ENERGY BALANCE THEORY

Energy balance at the Earth's surface largely controls the local climate. In the long term, the amount of energy reaching the surface must equal the amount of energy leaving the surface. If more energy reaches the surface than leaves the surface, the surface temperature will increase until energy input and output once again balance. Likewise, the surface temperature will decrease if more energy leaves than arrives at the surface (Oke, 1987; Arya, 2001').