Arctic Sea Ice Hits Record Low Extent 398
mdsolar writes "Arctic sea ice has hit a record low extent for the period of satellite observation. Further, this record has been set in August when the minimum annual sea ice extent (and the prior record) has always come in September. Further still, the ice is still retreating as rapidly as it was in June and July when normally the decrease of sea ice extent slows in August. It is thus possible the the final minimum sea ice extend for 2012 will be seen in October rather than September as has always occurred in the past. More than one monitoring effort agree on the existence of a new record."
NSIDC hasn't called the record yet (Score:5, Informative)
If you read response #4 of this update [realclimate.org] from Real Climate, you will see that the National Snow and Ice Data Centre hasn't called the record low yet (as of 26 Aug 2012 at 12:04 PM), since they use 5-day moving averages on their graphs. The graph referred to by the realclimate.org update and I think in the OP is based on daily data. The response is from Walt Meier of the NSIDC. I'll quote it here:
These are daily values, not the 5-day average, which is not quite at a record yet. Using a 5-day average removes some of the noise due to weather and other effects that cause small errors in the daily values. Thus the 5-day estimate is a more robust measure of sea ice changes. We will make an announcement on our web site when we have passed the current record: http://nsidc.org/arcticseaicenews/ [nsidc.org]
Walt Meier
NSIDC
I think however that there are other data series that do agree that the record has been broken, even with 5-day averages. Here is my favourite data compilation [google.com] for Arctic Sea Ice. It contains many different graphs from different sources. Taken together, the data paints a disturbing picture.
Re:Hmmm lets see (Score:5, Informative)
By October the air temp is around 13 degrees Fahrenheit. The max is 18 degrees and the minimum is 8 degrees. Days with Min Temp Below Freezing 31. http://www.climate-zone.com/climate/united-states/alaska/barrow/ [climate-zone.com] Are you still gonna stand by your statement of melting in October??
Do you realize how much time and energy it takes to raise a mass of water even one degree? It's why water temperature is always behind air temperature. You can have 90 degree days all through June and still have cold water temperatures yet still be swimming in September when air temperatures are cold. Water is a wonderful heat sink.
Re:Almost Meaningless (Score:5, Informative)
Explorers have unsuccessfully sought a Northwest Passage for a lot longer than climate satellites have been orbiting the Earth, so it seems likely that the current minimum dates back to pre-industrial times, at least.
But if you're arguing that "we need more research", then by all means advocate for that to your congressional representatives. House Republicans have been trying to slash climate research funding for a long time. They're also trying to prohibit [sciencemag.org] the National Institutes of Health from funding health economics studies. I wonder what issue that might relate to?
See no evil, hear no evil...
Re:Short term record (Score:5, Informative)
Actually the true statement IS that "this has never happened before". Ok, maybe it did happen in the interglacial periods before the last ice age, but not in the last 1450 years [skepticalscience.com] for which we have ice cores and other proxy data... and by that point there is no reason to not assume it to be true for the rest of our current interglacial unless you have some good argument to the contrary. You don't NEED the rather super-precise satellite observations we have for the last 33 years to make this kind of statement.
If this weren't so tragic it would be really funny seeing you deniers all flailing madly about for a way out of this one.
Re:Hmmm lets see (Score:5, Informative)
With regard to the Arctic melt of recent years, the VOLUME has been on a steady downward trend with little to no recovery. Extent is probably the easiest to measure but, by itself, it can be very misleading and is heavily influenced by waves and winds.
Re:Hmmm lets see (Score:5, Informative)
You are absolutely right. Volume and area are more telling than extent but as you say extent's the easiest to measure and volume the most difficult. With the launch of Cryosat [wikipedia.org] in April 2010 volume measurements are much more accurate now. That page I cited has graphs for extent, area and volume.
Re:Hmmm lets see (Score:5, Informative)
Cryosat uses SIRAL (a synthetic aperture radar/inferometric radar altimeter) to measure the altitude of sea ice over sea level to get the volume. Since ice is about 9% less dense than water you can tell how much ice there is by how high it sticks out of the water. If a 5 cm layer is at the surface then Cryosat will show an elevation of a little less 0.5 cm. I don't think there is such a thing as submerged lumps of thick multiyear ice because something would have to be holding it down to keep it from floating at the surface. There may be some relatively small areas that are held under water by mechanical pressure but they still contribute to the overall ice elevation in the area.
Climate sensitivity (Score:4, Informative)
The mathematics of thermal runaway on those old designs is nearly identical to the albedo-loss calculations of our ice caps.
I'd be brave enough to guess that they are the same equations with different constants and variables. When "thermal runaway" happens to a planet it's called a runaway greenhouse effect, Venus is to Earth as the fused transistor is to a working transistor. We're very unlikely to trigger such an effect here on Earth* but it's fairly well established science that Earth's ultimate fate is to look like a lot like Venus, ( in about 500Myrs from now). There are also -ve feedbacks, eg: expanding deserts tend to put dust in the air which has a cooling effect, as do sulfur emissions (which unfortunately also cause acid rain). When you add up all the +ve/-ve forcings and feedbacks you get a number called climate sensitivity [wikipedia.org]
Once the planet has undergone "thermal runaway" it's "fused", the oceans are gone forever, the hydrogen in the water vapor is split off in the upper atmosphere by radiation and over time leaks off into space due to it being the lightest element, carbon is now bound to the oxygen from the H2o to form more CO2, the process also makes the atmosphere denser since C is heaver than H. Earth is losing Hydrogen from the same process, it just taking a lot longer than it did for Mars and Venus (probably due to Earth's strong magnetic field.
* - James Hansen and other climatologists at the top of their field have warned that burning ALL known reserves of FF (coal/oil/gas/tar sands) would be more than enough forcing to trigger a RGH, sadly it's exactly what most industrial nations are planning to do over the next 250yrs or so (politicians can and do think long term when they want to). I say a RGH is unlikely since there are major signs that political will is growing to make the simplest and most cost effective adaptation we can to avert such an apocalyptic scenario, namely rebuilding the energy infrastructure ('a stitch in time' and all that). It's really not a huge drama when spread over 40-50yrs, on that time scale every nuke/coal generator on the planet has been planned, built and/or rebuilt, since I was born. We have to replace every one of them again in the next half century anyway. The only thing holding us up is a shrinking group of corporate Luddites such as Peabody coal who have not yet accepted their business model is as dead as the dinosaurs they are burning. If they hold on to coal for too long then bankruptcy will be a self-fulfilling prophecy as renewables take over and coal mines become virtually worthless.
Overpopulation is a myth (Score:4, Informative)
There is no global overpopulation. Some places (such as Japan) are already experiencing population aging and decline, which is bad in many ways. Other places (such as the USA and specially Europe) already have sub-replacement fertility rates, and their population only grows because of demographic lag and immigration. It is predicted the the European Union population (now at 503M) will reach zero natural population increase by 2015 and zero total population increase in 2035 (at 520M), then start declining.
The USA will grow from 310M in 2010 to 403M in 2050. [1]
Asia will increase from 4.2B in 2010 to 5.1B in 2050, then start declining. [2]
The only region that is really growing is Africa. It will increase from 1B in 2010 to 2.2B in 2050. [2] Then its population density will be 73/km2. [3] Compare that to the current population density in Portugal (115/km2), in South Korea (487/km2) and in Taiwan (641/km2). [4]
Global population is predicted to grow from 7B in 2011 to 9B in 2050 and 10B in 2100 [5] and start falling soon after [6].
And according to [7], 40-50% of America-produced food is thrown away. According to [8], 1/3 of the world food is thrown away.
And this does not take into account that people eat, just for pleasure, excessive quantities of resource-intensive food (such as meat). If Americans/Europeans want to help the poor, an easy way would be to decrease (say, by 30%) their diet of meat. This will immediately reduce food demand and, for double bonus, the saved money can be donated to charity. And much arable land is wasted on subsidized inefficient corn-based ethanol. You can lobby your government to stop that.
Plus, there does not seem to be a negative correlation between population density and GDP per capita. [9]
African hunger is not caused by overpopulation. It is caused by corrupt and authoritarian governments, and by guerrillas/terrorists motivated by Marxism, Islamism, ethnic hate or simply greed.
Overpopulation fear-mongering is very old - at least as old as Malthus. One of its more recent incarnations was the 1968 book "The Population Bomb", which predicted mass starvation to occur in the 1970s.
Anyway, for better or for worse, there is already strong action taken by individuals, foundations, and Western governments, to restrict fertility in Africa.
1 : http://esa.un.org/unpd/wpp/Analytical-Figures/htm/fig_11.htm [un.org]
2 : http://esa.un.org/unpd/wpp/Analytical-Figures/htm/fig_2.htm [un.org]
3 : According to [2], Africa will have 2.2B people in 2050, and according to Google[10] and Wikipedia [11], the area of Africa is 30,221,532 km2
4 : http://en.wikipedia.org/wiki/List_of_sovereign_states_and_dependent_territories_by_population_density [wikipedia.org]
5 : http://esa.un.org/unpd/wpp/Analytical-Figures/htm/fig_1.htm [un.org]
6 : http://esa.un.org/unpd/wpp/Analytical-Figures/htm/fig_6.htm [un.org]
7 : http://www.foodnavigator-usa.com/news/ng.asp?id=56376-us-wastes-half [foodnavigator-usa.com]
8 : http://www.fao.org/news/story/en/item/74192/icode/ [fao.org]
9 : http://sanamagan.wordpress.com/2011/03/10/population-population-density-gdp-per-capita-ppp/ [wordpress.com]
10 : https://www.google.co [google.com.br]