Methane Flux Measurements from Alaskan Thermokarst Lake Shorelines

Methane flux data from a remotely-sensed hotspot and various non-hotspot surfaces at Big Trail Lake, Alaska. Measurements were collected between July and December 2019 using a portable gas analyzer and bucket chambers, with flux reported in mmol CH4 m-2 hr-1 and mg CH4 m-2 d-1. The dataset was produced by ORNL_CLOUD and is available on multiple government data platforms.

Use Cases

• Validating airborne methane hotspot detections from instruments like AVIRIS-NG with ground-based flux measurements.
• Comparing emission rates between identified methane hotspots and representative non-hotspot surfaces within a thermokarst lake ecosystem.
• Analyzing diurnal or seasonal methane flux patterns from July to December 2019 in a sub-Arctic environment.
• Quantifying flux errors associated with different measurement techniques (UGGA vs. bucket chambers).
• Investigating the role of lake shorelines as sources of methane in permafrost landscapes.

Strengths

• Includes direct ground-truthing data collected approximately two hours after an AVIRIS-NG overflight for validation.
• Provides flux measurements in two standardized units (mmol CH4 m-2 hr-1 and mg CH4 m-2 d-1) for cross-study comparison.
• Covers a five-month sampling period from July 4 to December 4, 2019, capturing seasonal transition.
• Cross-platform presence on NASA Earthdata and Data.gov signals curation and importance.

Limitations

• Critical metadata conflicts exist: last updated date is listed as both 2019-12-14 and 2026-03-13 across sources.
• Core structural information is missing: row count, file size, and column names are unknown from all provided sources.
• Data collection was limited to daytime hours (09:35-17:32 local time), missing nocturnal flux dynamics.

Provenance

Source

ORNL_CLOUD

Collection Method

Field measurements using a Los Gatos Ultra-Portable Greenhouse Gas Analyzer (UGGA) at a hotspot and bucket chambers on non-hotspot surfaces.

Time Range

2019-07-04 to 2019-12 04

Freshness

2026-03-13 00:48:58.791054

Geography

Big Trail Lake (BTL) in the Goldstream Valley near Fairbanks, Alaska, USA.