Atmospheric Methane (global) vs Arctic Sea Ice Extent (September)

Atmospheric Methane (global) and Arctic Sea Ice Extent (September) correlate at r = -0.80 over 42 years (1984–2025), p < 0.0001. With the time trend removed, r = +0.52. Direction flips without the trend.

Verdict: Direction flips without the trend. The raw correlation is -0.80, but once each series' time trend is removed it becomes 0.52. The year-to-year movements run the opposite way to the long-run trends, so the headline number is misleading.

Pearson r: -0.80
p-value: < 0.0001
Years compared (n): 42 (1984–2025)
95% confidence interval: -0.89 to -0.65
Correlation with the time trend removed: +0.52

Sources

Atmospheric Methane (global) (ppb): NOAA GML. Global annual mean atmospheric methane from marine surface sites (NOAA GML).
Arctic Sea Ice Extent (September) (million km²): NSIDC. Mean Arctic sea ice extent in September, the yearly minimum (NSIDC Sea Ice Index).

Related pairs

Atmospheric Methane (global) vs US Natural Gas Consumption (r = +0.98)
Atmospheric Methane (global) vs US GDP per Capita (r = +0.98)
Atmospheric CO₂ (Mauna Loa) vs Atmospheric Methane (global) (r = +0.98)
Atmospheric Methane (global) vs US GDP (current US$) (r = +0.98)
Atmospheric Methane (global) vs US Median Age (r = +0.97)
Atmospheric Methane (global) vs US Population (r = +0.96)

Correlation does not imply causation. How the verdict is worked out.