Skip to main content
U.S. flag

An official website of the United States government

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Patterns and isotopic composition of greenhouse gases under ice in lakes of interior Alaska

Environmental Research Letters
By: , and 

Links

Abstract

Arctic and boreal lake greenhouse gas emissions (GHG) are an important component of regional carbon (C) budgets. Yet the magnitude and seasonal patterns of lake GHG emissions are poorly constrained, because sampling is limited in these remote landscapes, particularly during winter and shoulder seasons. To better define patterns of under ice GHG content (and emissions potential at spring thaw), we surveyed carbon dioxide (CO2) and methane (CH4) concentrations and stable isotopic composition during winter of 2017 in 13 lakes in the arid Yukon Flats Basin of interior Alaska, USA. Partial pressures of CO2 and CH4 ranged over three orders of magnitude, were positively correlated, and CO2 exceeded CH4 at all but one site. Shallow, organic matter-rich lakes located at lower elevations tended to have the highest concentrations of both gases, though CH4 content was more heterogeneous and only abundant in oxygen-depleted lakes, while CO2 was negatively correlated to oxygen content. Isotopic values of CO2 spanned a narrow range (−10‰ to −23‰) compared to CH4, which ranged over 50‰ (−19‰ to −71‰), indicating CH4 source pathways and sink strength varied widely between lakes. Miller-Tans and Keeling plots qualitatively suggested two groups of lakes were present; one with isotopically enriched source CH4 possibly more dominated by acetoclastic methanogenesis, and one with depleted signatures suggesting a dominance of the hydrogenotrophic production. Overall, regional lake differences in winter under ice GHG content appear to track landscape position, oxygen, and organic matter content and composition, causing patterns to vary widely even within a relatively small geographic area of interior Alaska.

Study Area

Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Patterns and isotopic composition of greenhouse gases under ice in lakes of interior Alaska
Series title Environmental Research Letters
DOI 10.1088/1748-9326/abb493
Volume 15
Issue 10
Year Published 2020
Language English
Publisher IOP Science
Contributing office(s) WMA - Earth System Processes Division
Description 105016, 12 p.
Country United States
State Alaska
Google Analytic Metrics Metrics page
Additional metadata about this publication, not found in other parts of the page is in this table