A high-altitude balloon platform for determining exchange of carbon dioxide over agricultural landscapes
The exchange of carbon dioxide between the terrestrial biosphere and the atmosphere is a key process in the global carbon cycle. Given emissions from fossil fuel combustion and the appropriation of net primary productivity by human activities, understanding the carbon dioxide exchange of cropland ag...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2016-11-01
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| Series: | Atmospheric Measurement Techniques |
| Online Access: | http://www.atmos-meas-tech.net/9/5707/2016/amt-9-5707-2016.pdf |
| Summary: | The exchange of carbon dioxide between the terrestrial biosphere
and the atmosphere is a key process in the global carbon cycle. Given
emissions from fossil fuel combustion and the appropriation of net primary
productivity by human activities, understanding the carbon dioxide exchange
of cropland agroecosystems is critical for evaluating future trajectories of
climate change. In addition, human manipulation of agroecosystems has been
proposed as a technique of removing carbon dioxide from the atmosphere via
practices such as no-tillage and cover crops. We propose a novel method of
measuring the exchange of carbon dioxide over croplands using a high-altitude
balloon (HAB) platform. The HAB methodology measures two sequential vertical
profiles of carbon dioxide mixing ratio, and the surface exchange is
calculated using a fixed-mass column approach. This methodology is relatively
inexpensive, does not rely on any assumptions besides spatial homogeneity (no
horizontal advection) and provides data over a spatial scale between
stationary flux towers and satellite-based inversion calculations. The HAB
methodology was employed during the 2014 and 2015 growing seasons in central
Illinois, and the results are compared to satellite-based NDVI values and a
flux tower located relatively near the launch site in Bondville, Illinois.
These initial favorable results demonstrate the utility of the methodology
for providing carbon dioxide exchange data over a large (10–100 km) spatial
area. One drawback is its relatively limited temporal coverage. While
recruiting citizen scientists to perform the launches could provide a more
extensive dataset, the HAB methodology is not appropriate for providing
estimates of net annual carbon dioxide exchange. Instead, a HAB dataset could
provide an important check for upscaling flux tower results and verifying
satellite-derived exchange estimates. |
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| ISSN: | 1867-1381 1867-8548 |