The camera shoots through two people looking at each other and just visible on the edges of the frame. In the center, a man crouches next to a gray uncrewed fixed-wing aircraft with a yellow nose cone.

A man with long black hair and a black beard, wearing a khaki green jacket and large tan hat and standing in a bright green forest, works on a round white box on a black string.

CRATER

The CRATER (Costa Rica Airborne research on foresT Ecosystem Response to volcanic emissions) project seeks to advance our understanding of the interactions between volcanic gas emissions and tropical ecosystems.

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TYPE

Airborne/Atmospheric Science, Ecology

FIELDWORK

Summer 2025

PRINCIPAL INVESTIGATOR

Jay Tomlin

UAS Measures Emissions

Jay Tomlin Launches the S2

In this composite image, CRATER science principal investigator Jay Tomlin launches the S2 Black Swift uncrewed aircraft system (UAS) into the sky at Rincon de la Vieja National Park, Costa Rica, during the 2025 campaign. CRATER (Costa Rica Airborne research on foresT Ecosystem Response to volcanic emissions), is a NASA-led project investigating the use of an uncrewed aircraft for volcanic trace gas sampling, in order to better understand the impact of elevated carbon dioxide emissions on vegetation. Credits: NASA/Milan Loiacono

UAS Measures Emissions

A man in an orange jacket and black pants stands in a field of tan and green grass, looking at a small gray fixed-wing aircraft with a yellow nose cone, sitting on a silver launcher. In this composite image, the aircraft is pictured again and again across the sky, moving away from the camera. In the background is a blueish mountain and cloudy skies.

Overview

CRATER seeks to increase our understanding of the interaction between persistent gas emission and tropical ecosystems, using the S2 Black Swift uncrewed aircraft system (UAS) to measure trace gas concentrations around Rincón de la Vieja Volcano, Costa Rica.

What is CRATER?

CRATER, which stands for Costa Rica Airborne research on foresT Ecosystem Response to volcanic gas emissions, aims to characterize and track the location, distribution, and fate of these gases.

These low-altitude airborne observations, when combined with existing ground-based datasets available from collaborators on site, will provide a more complete picture of how persistent volcanic emissions influence surrounding ecosystems.

Visible Imagery

vegetation map

A map of a dark green forest has a light green textured diamond in the middle.

Using high-resolution imagery captured by the S2 Black Swift UAS, the CRATER team create a orthomosaic map.

A map of a dark green forest has a false-color diamond in the middle, made up of bright green, yellow, and red dots.

Using high-resolution imagery captured by the S2 Black Swift UAS, the CRATER team used a metric called NDVI (normalized difference vegetation index) to create a vegetation map, which measures the amount of green vegetation in order to assess vegetation health.

NASA/CRATER

Using high-resolution imagery captured by the S2 Black Swift UAS, the CRATER team create a orthomosaic map.

NASA/CRATER

Visible Imagery

vegetation map

Orthomosaic and Vegetation Mapping

Using high-resolution imagery captured by the S2 Black Swift UAS, the CRATER team was able to create two maps. On the left, an orthomosaic map uses a composite of overlapping images to create a high-resolution image of the forest. On the right, a vegetation map uses a metric called VARI (Visible Atmospherically Resistant Index), which measures the amount of green vegetation to assess vegetation health.

CRATER’s Science Objectives

The Costa Rica Airborne research on foresT Ecosystem Response to volcanic emissions (CRATER) mission seeks to advance our understanding of the interactions between persistent volcanic gas emission and tropical ecosystems. NASA Ames Research Center’s Flight Operations and Earth Science Division collaborate with Black Swift Technologies LLC to deploy an Ames fixed-wing electric S2 uncrewed aircraft system (UAS) at Rincón de la Vieja Volcano, Costa Rica with support from University of Costa Rica collaborators. The S2 will collect high-resolution infrared and visual imagery, and trace gas concentration data (CO2, H2O, H2S, SO2, and SO2 plume cross-sections via mini-DOAS) along the volcano’s south-southeastern flank.

This mission will enable spot quantification of “diffuse” volcanic CO2 flux as this “cold” volcanic gas continuously seeps into and through tropical forests from below. It will also improve our understanding of how these diffuse emissions and those from the crater vent are transported and dispersed along the flanks of Rincón de la Vieja, and how surrounding and overlaying vegetation responds to such elevated CO2. We aim to characterize plume structure and distribution, and to identify volcanic CO2 transport pathways. These near surface (<120 m) airborne observations, when combined with existing ground-based datasets available from our collaborators on site, will provide a more complete picture of how persistent volcanic gas emissions influence surrounding ecosystems. The region’s unique exposure to elevated CO2 offers a natural laboratory to explore how tropical vegetation responds to long-term gas inputs, insight that may illuminate broader ecological consequences of rising atmospheric CO2 levels and reveal early indicators of volcanic unrest.

Together, these areas of research will answer:

How does persistent volcanic CO2 affect surrounding vegetation, and can remote sensing detect these changes?
How do volcanic CO2 emissions from the crater compare in magnitude and spatial distribution to persistent, variable emissions from surface vents?
How do continuously released gases disperse, including elusive downslope flow of CO2, influence local variability in ecosystem response and volcanic emission changes
How effective are UAS-based methods for detecting and quantifying gas fluxes in rugged volcanic environments compared to ground-based or satellite methods? What lessons from this campaign can inform safe, efficient, and robust operation protocols of future UAS deployments in challenging terrain?

What can volcano emissions teach us about tropical ecosystems?

Volcanoes are effective natural laboratories. Persistent volcanic gas emissions offer a unique opportunity to study how tropical ecosystems respond to elevated levels of carbon dioxide (CO2), providing insight into how rising atmospheric CO2 may impact forest health, growth, and resilience on a changing planet.