Field Notes from NASA SnowEx Grand Mesa Campaign

Overview

In this bonus Field Notes episode, Jessica Mersdorf follows NASA's SnowEx 2020 team to Grand Mesa, Colorado, to document how scientists measure snow depth, density and particle size using both ground snow pits and airborne SWISAR radar. The episode highlights the climate and water relevance of snow and the realities of field campaigns.

• Ground and air measurements illuminate snow properties and their role in Earth's climate system.
• Audio diaries capture daily weather, sky conditions and personal reflections from the field.
• Team dynamics, altitude sickness and snowmobile logistics shape the campaign experience.
• Snowpack layering and albedo underscore snow's importance for temperature regulation and water resources.

Introduction

The podcast follows Jessica Mersdorf, an Earth science writer, as she joins NASA's SnowEx 2020 team on Grand Mesa, Colorado. The episode frames field campaigns as a dynamic process where scientists gather measurements in environments ranging from hot to cold. SnowEx is a project dedicated to researching snow properties such as depth, density and particle size using a combination of ground instruments and airborne radar and radiometry.

Setting and Campaign Context

Grand Mesa presents a vast white table of snow with sparse tree clumps and a sense of isolation heightened by altitude. The field campaign is designed to cover diverse snow conditions, with snow playing a critical role in climate regulation through sunlight reflection and in providing drinking water for many communities. The host records how the landscape motivates scientists and underscores snow as a key component of Earth’s ecosystem.

SnowEx Components and Instruments

The SnowEx program comprises airborne and ground components. The airborne work centers on SWISAR, the Snow Water Equivalent Synthetic Aperture Radar and Radiometer, which maps snow properties from above. On the ground, scientists perform measurements in snow pits and conduct depth and density assessments with instruments carried on snowmobiles. The team planned 146 snow pits and ultimately completed 153, illustrating the complexities of field work and data collection in challenging environments.

Field Methods and Observations

Snow pits are dug to reveal the layering of snow from the surface to the ground, illustrating how wind-packed layers and denser strata differ in water content. The ground component involves driving in clockwise spirals to create crop-circle like patterns, with pits at the center to capture measurements by hand. The combination of airborne and ground measurements enables a comprehensive view of snowpack structure, reflectivity, and its variability across the landscape.

Personal Experience and Challenges

The host describes a mix of awe and hardship. Altitude sickness, frigid temperatures and strong winds contribute to a harsh but rewarding environment. The people involved in the campaign become lifelines, and the isolation is balanced by moments of extraordinary beauty and scientific purpose. Jessica also records nervous anticipation about snowmobile rides and notes how rapid driving conditions affect safety and ground coverage.

Scientific Significance

The SnowEx measurements feed into broader questions about how snow affects Earth’s energy balance and water resources. By comparing airborne SWISAR data with ground-based pits and hand measurements, the campaign aims to improve snow depth, density and layering estimates, which are essential for climate models and water management strategies in snow-prone regions.

Conclusion

As the episode closes, the field notes emphasize that science is a living process involving real people in real places. The narrator expresses both pride in adapting to field conditions and sadness at leaving a landscape that proved magical and transformative.