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The Mass Balance of Sweden's Storglaciaren
Linderholm, H.W., Jansson, P. and Chen, D. 2007. A high-resolution reconstruction of Storglaciaren mass balance back to 1780/81 using tree-ring and circulation indices. Quaternary Research 67: 12-20.

The authors begin the report of their work by stating that "in a time when global warming is a key issue in climate research, it is important to understand the behaviour of natural climate variability." Noting that "glaciers are recognized as good climate indicators and their mass balance records and glacier extent variations, as well as ice-core data, can be used to yield information on past climate variability," they thus proceed to see what they can learn in this regard from what they say is "the world's longest ongoing continuous mass-balance record" of "Storglaciaren in northernmost Sweden," which they report "is generally well correlated to glaciers included in the regional mass balance program (Holmlund and Jansson, 1999), suggesting that it represents northern Swedish glaciers."

What was done
Linderholm et al. say they "reconstructed summer (bS) and winter (bW) mass balances separately back to the mass balance year 1780/81 with annual resolution" based on "tree-ring data for bS and a set of circulation indices, based on sea-level pressure, for bW."

What was learned
The four researchers report that both proxies had correlation coefficients with their respective mass balance components of about 0.7, and that "the reconstructed net balance (bN) of Storglaciaren was well correlated to the observations during 1946-1980 (r = 0.8, p < 0.05)." The results of their work are depicted in the figure below, where we have also plotted the contemporaneous history of the atmosphere's CO2 concentration.

The cumulative reconstructed net mass balance (bN) history of Sweden's Storglaciaren (to which we have added the fit-by-eye descending linear relationship), in blue, and the history of the atmosphere's CO2 concentration, in red. Adapted from Linderholm et al. (2007).

What it means
In viewing the results of Linderholm et al.'s work, it should be evident to all that the historical increase in the air's CO2 content has had absolutely no discernable impact whatsoever on the net mass balance history of Sweden's Storglaciaren over the past two and a quarter centuries. Whereas the mean rate-of-rise of the air's CO2 concentration over the last half-century of Storglaciaren mass balance data is fully fifteen times greater than what it was over the first half-century of mass balance data (and some forty times greater if the first and last quarter-centuries are considered), there has been no sign of any change in the long-term trend of Storglaciaren's net mass balance, which just keeps doing its own thing, seemingly totally oblivious to the concurrent huge acceleration in the rate-of-rise of the atmosphere's CO2 concentration.

Holmlund, P. and Jansson, P. 1999. The Tarfala mass balance programme. Geografiska Annaler 81A: 621-631.

Reviewed 4 July 2007