My effect is so much more important than your effect.
Please keep comments appropriate to the "Climatic Effects of a Blue Ocean Event" forum. This is not a catch-all forum for climate change or climate policy discussion. 'Climatic' means inappropriate for local Arctic-only seasonal impacts as these have their own forums.
Consider discussing and developing
your favorite BOE climatic effect based on other recent scientific journal articles. Just making bald assertions or intuiting is
not going to work quantitatively given the complexity of planetary climate systems. Try
https://scholar.google.com/ to see where a given subject is at. Full text can always be located at
https://sci-hub.se/.
Rightly or wrongly, the vast majority of climate science focuses on long-term build-up of greenhouse gases and their effects at NH mid-latitudes where most white people live and most of their food is grown. Rightly or wrongly, messaging is currently centered on CO2 levels and what can be done to reduce it (more trees, less beef consumption, fossil fuels, consumerism). All this is incredibly important but unacceptably off-topic given this forum's
restricted remit.
The authors here framed their result in the above context, the trillion extra tons. Their calculated effect on annual heat retention alone is enough by itself to seriously undercut current global policy planning on climate change and to significantly offset benefits from planting trees, going vegan and riding wind-powered electric bicycles. Yes, lots of other feedbacks like ESAS methane could pile on but there are forums for those too.
My subsequent posts will be looking into the calculation itself and its reliability. Science does not arrive written on clay tablets. Already, an alternative method has been published. Those authors find less of an effect but actually their results still call for a massive effect (which they call 'modest'). Still, both calculations could be wrong or have too high a level of uncertainty to deserve concern priority.
To repeat, the loss of the planet's primary climate-buffering refrigerator (seasonal high latitude albedo) is only one aspect of downstream consequences of fractional loss of Arctic sea ice increasingly matching the insolation season.
BOE events do not happen overnight on Sept 14th but instead will have a long lead-up of increasing areas of low albedo open water, a much better match to peak insolation than mid-Sep dates which don't match at all. More sunlight absorbed means less reflected up and, after cloud and atmospheric processes, less incident sunlight escaping out to space.
The papers under consideration look only at this: heat retained = TOE input - TOE output above 60ºN and attributable to massive sea ice loss.
The three articles do not aspire to represent all downstream aspects nor to compare its impacts to all others; they merely assert it is large and real. If you find scientific errors missed by peer reviewers -- and that happens -- please document specifics. Alternatively, write a separate post based on different articles about your pet effect.
The first graphic is taken from a pair of easy-read classics by Perovich, Stroeve and others. They follow the solar insolation distribution during seasonal evolution of the surface, the complement of the Pistone 2019 independent top of atmosphere observations and projections.
Solar partitioning in a changing Arctic sea-ice cover
DK Perovich et al
Annals of Glaciology 52(57) 2011
"The daily values of albedo depend on the local onset dates of melt and freeze-up. The albedo sequence includes melt ponds, assuming they follow an evolution similar to that observed by Perovich and others (2002). Using the method of Markus and others (2009), daily averaged satellite passive microwave temperatures are used to map four onset dates for each grid cell for each year: early melt, full melt, early freeze-up and full freeze-up.
"Briefly, the melt season is determined using temporal changes in brightness temperatures at 37 GHz and temporal changes in the gradient ratio between 19 and 37 GHz
1. Before melt onset the snow albedo is 0.85.
2. At early melt the albedo decreases to 0.81.
3. Starting with full melt, there is a linear decrease to 0.71 in 15 days.
4. For the next 6 days, decrease from 0.70 to 0.50.
5. Albedo decreases by 0.0029 d–1 (but to no less than 0.2).
6. At early freeze-up set albedo to 0.46, representing some ponds freezing.
7. At full freeze-up, albedo increases by 0.026 per day to 0.85."
Increasing solar heating of the Arctic Ocean and adjacent seas, 1979–2005:
DK Perovich et al
Geophys. Res. Lett., 34(19), L19505. (10.1029/2007GL031480.)
The graphical time series will look at incipient fractional BOE: open water in the Arctic Basin at the time of maximum insolation (summer solstice, June 21). There is a surprising amount of open water already on that date and has been for years. However the AMSR2 record used is not long enough to distinguish trend from natural variability. That is a fool's errand anyway if the New Arctic is qualitatively different. However the unweighted locational average is still instructive.
The animation will show open water for the years 2013-20 (since 2012 data starts later). The second graphic will provide the average geographic distribution for open water for eight years on the solstice and later dates. A preliminary version gives the idea.
This average is calculated graphically to sidestep the flawed netCDF. Select open water blue in each year and color it 240 white (out of 256 pure white). If every year has open water at a given pixel location, then all the pixels will be 240 and the average atoo in the output graphic. If 7 years are open water, then 7/8 or 210 is the output, and so on down to 1/8 yielding 30, not quite black.
Thus the average-graphic is strongly but accurately binned into a 8-10 colors (allowing a few extra for land and and pole markers. The image can then be recolored with any discrete palette without disturbing quantitative accuracy.
To weight recent years more heavily, their layer simply needs to be duplicated by the chosen weighting number.