# Webster 2018: Background levels of methane in Mars' atmosphere show strong seasonal variations

> Christopher R. Webster, Paul R. Mahaffy, Sushil K. Atreya et al., 2018. 8 records on Mysteries Department cite it. The seasonal-cycle claim.

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[Sources](https://mysteriesdept.com/sources)[Mars methane puzzle](https://mysteriesdept.com/mysteries/mars-methane)Webster 2018

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# Background levels of methane in Mars' atmosphere show strong seasonal variations

Christopher R. Webster, Paul R. Mahaffy, Sushil K. Atreya et al., 2018. _Science 360(6393), 1093–1096_.

Five years of TLS measurements: background mean 0.41 ± 0.16 ppbv with a repeatable seasonal cycle from 0.24 to 0.65 ppbv, larger than predicted from ultraviolet breakdown of organics or the pressure cycle, plus spikes of about 7 ppbv.

**Mars methane puzzle** Articledoi: **[10.1126/science.aaq0131](https://doi.org/10.1126/science.aaq0131)** Checked against the original0

## What it's used for here

The seasonal-cycle claim.

## Cited by on this site 8 records

[Background methane varies seasonally from about 0.24 to 0.65 ppbv.](https://mysteriesdept.com/mysteries/mars-methane/answers/ANS0D7EY23G5D79/background-methane-varies-seasonally-from-about-0-24-to-0-65)

Answer

ANS

[Curiosity SAM-TLS methane measurements, Gale crater](https://mysteriesdept.com/mysteries/mars-methane/artifacts/ART0D7EY7Z04A03/curiosity-sam-tls-methane-measurements-gale-crater)

ART

[A strong, repeatable seasonal variation over five years, larger than predicted from known processes.](https://mysteriesdept.com/mysteries/mars-methane/evidence/EVD0D7EY2BA435M/a-strong-repeatable-seasonal-variation-over-five-years)

Evidence

EVD

[Background 0.41 ± 0.16 ppbv over five years with spikes of about 7 ppbv.](https://mysteriesdept.com/mysteries/mars-methane/evidence/EVD0D7EXY6G39D8/background-0-41-0-16-ppbv-over-five-years-with-spikes-of)

Evidence

EVD

[TLS reports a seasonal cycle in background methane](https://mysteriesdept.com/mysteries/mars-methane/events/EVT0D7EXVGJ2GBC/tls-reports-a-seasonal-cycle-in-background-methane)

EVT

[Christopher R. Webster](https://mysteriesdept.com/mysteries/mars-methane/people/FIG0D7EXRTM292B/christopher-r-webster)

FIG

[The Mars methane puzzle](https://mysteriesdept.com/mysteries/mars-methane)

The mystery article

MYS

[Does the background follow a seasonal cycle?](https://mysteriesdept.com/mysteries/mars-methane/questions/QST0D7EXX785WEM/does-the-background-follow-a-seasonal-cycle)

Question

QST

## Cite it

```
Webster, C. R., Mahaffy, P. R., Atreya, S. K., Moores, J. E., & et al. (2018). Background levels of methane in Mars' atmosphere show strong seasonal variations. Science 360(6393), 1093–1096. https://doi.org/10.1126/science.aaq0131
```

[Read it free at doi.org](https://doi.org/10.1126/science.aaq0131)

Key

**SRC** 0D7EXME03TED

Kind

Journal article

Rights

The publisher's

Kept

27 Oct 2026, for editors

Checked

Against the published article

Added by

[apollo](https://mysteriesdept.com/u/apollo)

The record

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