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Title: High Intra‐Seasonal Variability in Greenhouse Gas Emissions From Temperate Constructed Ponds
Abstract Inland waters play a major role in global greenhouse gas (GHG) budgets. The smallest of these systems (i.e., ponds) have a particularly large—but poorly constrained—emissions footprint at the global scale. Much of this uncertainty is due to a poor understanding of temporal variability in emissions. Here, we conducted high‐resolution temporal sampling to quantify GHG exchange between four temperate constructed ponds and the atmosphere on an annual basis. We show these ponds are a net source of GHGs to the atmosphere (564.4 g CO2‐eq m−2 yr−1), driven by highly temporally variable diffusive methane (CH4) emissions. Diffusive CH4release to the atmosphere was twice as high during periods when the ponds had a stratified water column than when it was mixed. Ebullitive CH4release was also higher during stratification. Building ponds to favor mixed conditions thus presents an opportunity to minimize the global GHG footprint of future pond construction.  more » « less
Award ID(s):
2143449
PAR ID:
10490762
Author(s) / Creator(s):
;
Publisher / Repository:
Geophysical Research Letters
Date Published:
Journal Name:
Geophysical Research Letters
Volume:
50
Issue:
18
ISSN:
0094-8276
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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