Instrument Record

Category · cryosphere

Every year on one seasonal clock.

Is this year’s cycle running low, and is the September Arctic still trending down? Monthly extent for both poles, plus a seasonal envelope of every year overlaid on the calendar.

Arctic vs Antarctic monthly extent

NSIDC Sea Ice Index v4, 15% concentration

Arctic sea -0.521 10⁶ km²/decadeAntarctic sea -0.077 10⁶ km²/decade

Seasonal envelope — every year on one clock

Faint lines: full record. Bright: last 8 years. White: current year.

Arctic September is the well-known decline. Antarctic extent is noisier, with a high plateau then a drop after 2016. Months on the x-axis replace a stack of monthly maps.

Northern hemisphere snow cover

Rutgers Global Snow Lab, million km²

Companion desks

Same project, other questions.

They are not extra series on these charts — they are the arguments about ice versus stomata, the 20th-century blade, the ¹³C fingerprint, the 1988 polar forecasts, and what CERES actually attributes the last 26 years to.

Stomata vs Ice

Plant leaves keep a growing-season count of pores. Antarctic ice keeps bubbles of old air. Ice-core CO₂ is heavily smoothed; stomatal series still carry century-scale swings that only meet the ice at the instrumental splice.

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Hockey Stick Lab

Mann, Bradley & Hughes 1998 made a shaft-and-blade by overweighting the Sheep Mountain bristlecone (CA534) by as much as 390×. Strip that weight and the 1910–1938 climb is already there. Drag the weight yourself against HadCRUT5.

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δ¹³C Ledger

The “fossil isotopic signature” is not a raw intercept. Station Keeling plots sit near −13‰; the textbook −28‰ is an isoflux term after gravity, diffusion, blank and scale corrections. The ledger separates observation from the model step.

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Arctic and Antarctic vs the 1988 estimates

1988-era scenarios warmed both poles under well-mixed greenhouse gas. The split is not that: Arctic air rose; Antarctic did not. Sea-level rise since 1900 is expansion-scale, not a melt pulse matching those polar-ice forecasts.

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NZ Atlas

Nikolov & Zeller and Goessling, Rackow & Jung land on the same CERES fact: the last ~26 years of warming track absorbed sunlight from a falling planetary albedo. They split on story; the satellite number they both use is albedo, not CO₂ forcing.

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