Tag Archives: Ice Caps

Global warming’s effects are coming on faster than previously thought.

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Arctic sea ice decline happened faster than expected. This has the effect of accelerating global warming because less of the Sun’s energy is reflected back into space by ice.

SeaIceDecline_591

Northern Hemisphere snow also sends some of that energy back into space. The amount of snow cover we have is also declining.

Difference from average annual snow extent since 1971, compared to the 1966-2010 average (dashed line). Snow extents have largely been below-average since the late1980s. Graph adapted from Figure 1.1 (h) in the 2012 BAMS State of the Climate report.
Difference from average annual snow extent since 1971, compared to the 1966-2010 average (dashed line). Snow extents have largely been below-average since the late1980s. Graph adapted from Figure 1.1 (h) in the 2012 BAMS State of the Climate report.

The warming of the Arctic region is also probably causing an increase in the amount of CO2 and Methane, previously frozen in permafrost or offshore, that is going into the atmosphere. For this and other reasons, Methane, along with other greenhouse gases, are increasing. I quickly add that stories you’ve heard of a civilization “methane bomb” in the Arctic are not supported by the best available science. But these additional greenhouse gases still count.

Global average abundances of the major, well-mixed, long-lived greenhouse gases - carbon dioxide, methane, nitrous oxide, CFC-12 and CFC-11 - from the NOAA global air sampling network are plotted since the beginning of 1979. These gases account for about 96% of the direct radiative forcing by long-lived greenhouse gases since 1750. The remaining 4% is contributed by an assortment of 15 minor halogenated gases including HCFC-22 and HFC-134a (see text). Methane data before 1983 are annual averages from D. Etheridge [Etheridge et al., 1998], adjusted to the NOAA calibration scale [Dlugokencky et al., 2005].
Global average abundances of the major, well-mixed, long-lived greenhouse gases – carbon dioxide, methane, nitrous oxide, CFC-12 and CFC-11 – from the NOAA global air sampling network are plotted since the beginning of 1979. These gases account for about 96% of the direct radiative forcing by long-lived greenhouse gases since 1750. The remaining 4% is contributed by an assortment of 15 minor halogenated gases including HCFC-22 and HFC-134a (see text). Methane data before 1983 are annual averages from D. Etheridge [Etheridge et al., 1998], adjusted to the NOAA calibration scale [Dlugokencky et al., 2005].

Now we are learning that glacial ice, in particular in Antarctica, is melting faster than expected.

That video is from a recent post by Peter Sinclair, who has more on glacial melting.

We knew a lot of the additional heat (from global warming) was going into the oceans, but now we have learned that a LOT of this heat is going into the ocean. This heat goes in and out, so what has been going in will likely be going out (into the atmosphere).

90% of the Earth's energy balance involves the ocean's heat, shown here. Note that there is no current pause, and that surface temperature estimates (see graph above) tend to underestimate the total amount of anthropogenic global warming because much of this heat, routinely, goes into the ocean. We can expect some of this heat to return to the atmosphere in coming years.
90% of the Earth’s energy balance involves the ocean’s heat, shown here. Note that there is no current pause, and that surface temperature estimates (see graph above) tend to underestimate the total amount of anthropogenic global warming because much of this heat, routinely, goes into the ocean. We can expect some of this heat to return to the atmosphere in coming years.

(See also this post by Joe Romm.)

This causes me to look at a graph like this …

Figure SPM.5. Solid lines are multi-model global averages of surface warming (relative to 1980–1999) for the scenarios A2, A1B and B1, shown as continuations of the 20th century simulations. Shading denotes the ±1 standard deviation range of individual model annual averages. The orange line is for the experiment where concentrations were held constant at year 2000 values. The grey bars at right indicate the best estimate (solid line within each bar) and the likely range assessed for the six SRES marker scenarios. The assessment of the best estimate and likely ranges in the grey bars includes the AOGCMs in the left part of the figure, as well as results from a hierarchy of independent models and observational constraints. {Figures 10.4 and 10.29}
Figure SPM.5. Solid lines are multi-model global averages of surface warming (relative to 1980–1999) for the scenarios A2, A1B and B1, shown as continuations of the 20th century simulations. Shading denotes the ±1 standard deviation range of individual model annual averages. The orange line is for the experiment where concentrations were held constant at year 2000 values. The grey bars at right indicate the best estimate (solid line within each bar) and the likely range assessed for the six SRES marker scenarios. The assessment of the best estimate and likely ranges in the grey bars includes the AOGCMs in the left part of the figure, as well as results from a hierarchy of independent models and observational constraints. {Figures 10.4 and 10.29}

… and figure that warming over coming decades will be at, near, or even above, the range previously estimated.