chubbs

Northern oceans have continued to warm while el-nino fades cooling the tropics. See also: http://www.esrl.noaa.gov/psd/map/clim/sst.anom.anim.year.html

It is surprising how close CT SIA came to 2012. The series of storms in August may also have played a role by enhancing bottom melt.

NSIDC extent dropped 120k on 9/6 to 4083k clinching 2nd place.

Yes, good job flagging 4mil as a reasonable prospect at the start of the year

Would expect above average extent losses to close out the melt season due to the large areas of low concentration ice, good melting momentum, and relatively mild weather to start September particularly over the Laptev.

Here is 70-80N on the Pacific side covering most of the rest of the Arctic Ocean. There are some year-to-year differences, particularly this year, but the overall trend is similar.

Cool season 80-90N has warmed by roughly 4C in the past 20 years, so unless things slow down, 2C is not that far away.

Down 360k in the past 3 days. With this late area drop, looks like 2016 is going to separate from 2011/2007 on CT SIA.

Could also be cloud/precip/ice movement since it reversed last night with a 147k amsr2 area drop. Day-to-day trends have been variable but area is still dropping at a good clip averaged over the past week or so.

Yes dipole would be much worse in June or July. I favor 2 or 3 on area.

You were thinking 4-6'th at the start of the stormy period. Is that still your call?

Big area losses in the CAB the past couple of days. With the stormy pattern forecast to persist for the next week, may get open water close to the pole.

Per the PV pattern, 12z euro/gfs forecasting strengthening low moving from Laptev/ESS to CAB in 4/5 days, euro bottoms out at 966, gfs at 971.

Hoth, on 07 Dec 2015 - 7:02 PM, said: 1) Do you know of any peer-reviewed literature out there that provide a percentage of warming that is directly attributable to Man’s activities? I’ve never seen anyone offer a quantitative breakdown or range. Per chart below, the IPCC estimated that almost all of the temperature increase since 1950 was due to man-made forcing. 2) The article you posted above states that the earth is even more sensitive to carbon dioxide than originally thought. Why then, since carbon emissions have been rising almost exponentially for decades with the rapid development of BRIC nations, has temperature maintained a more or less linear rate of increase? (Some might say there’s been a pause). Shouldn’t such sensitivity and strong correlation suggest we should have observed rapid temperature increase for some time? Per chart below, temperature is well correlated with atmospheric CO2. Note that GHG forcing is proportional to the log of CO2. Other man-made GHGs like methane and CFC's also have an impact as well as aerosals which have a cooling effect. The rate of increase in man-made GHG forcing has actually slowed a little since the 1980s due to the Montreal Protocol which dramatically reduced CFC emissions and a slowdown in the rate of methane increase.

Yes it is a step in the right direction but will need follow-up to be meaningful. Main reason it is voluntary is US and our strong political opposition to action.

CO2 emissions show recent evidence of stabilizing with a small 0.6% increase in 2014 and a 0.6% decrease projected for 2015. Main factors are a big slowdown in the growth of coal use in China and a general trend to less coal and more renewable energy elsewhere. While the future path is uncertain, it looks like following the unmitigated RCP8.5 pathway is becoming less likely. http://www.globalcarbonproject.org/carbonbudget/

2) The article you posted above states that the earth is even more sensitive to carbon dioxide than originally thought. Why then, since carbon emissions have been rising almost exponentially for decades with the rapid development of BRIC nations, has temperature maintained a more or less linear rate of increase? (Some might say there’s been a pause). Shouldn’t such sensitivity and strong correlation suggest we should have observed rapid temperature increase for some time? A couple of points: 1) GHG forcing is proportional to the log of CO2 in the atmosphere. So an exponential or constant percentage increase in CO2 in the atmosphere results in a linear increase in temperature. If atmospheric CO2 doubles it will take twice as much CO2 to have the same effect. 2) The yearly percentage increase in atmospheric CO2 depends on: man-made CO2 emissions, natural carbon sinks and the amount of CO2 already in the atmosphere. Recently atmospheric CO2 has been increasing by about 0.5% per year. This percentage rate has increased slowly and unevenly from roughly 0.3% per year in the 1960s. 3) The rate of increase in non-CO2 man-made GHGs, like methane and refrigerants, has slowed down since the 1980s. When you add the impact of non-CO2 GHG to CO2, the resulting equivalent CO2 concentration has been increasing by roughly 0.6% per year recently. 4) The rate of increase in man-made aerosals, which have a cooling effect, has slowed considerably since roughly 1970. When you put it all together man-made forcing increased slowly up to roughly 1970 and then began to increase faster in a roughly linear manner. The long-term global temperature trend fits the man-made forcing trend well. Note that man-made forcing increases slowly from year-to-year, so short-term pauses or spikes in temperatures from natural causes are to be expected.

Here is a recent video from Alley on CO2's role in past climates. This "minor" gas has kept the earth's climate well suited for life. http://climatestate.com/2015/07/31/richard-alley-4-6-billion-years-of-earths-climate-history-the-role-of-co2/

Yes we will have to adapt. We are inching to a global solution. The physics will push us there eventually.

Climate change is a global problem and will require a global solution. A carbon tax applied equally across the globe is the best solution. This would allow market economics to reduce emissions in the most cost-effective manner. Driving the best long-term energy technologies and regional emission strategies. It may or may not be cheaper to reduce emissions in China vs the US or other countries. Note that our current system is sub-optimal and has resulted in over-investment in fossil fuels, particularly coal. We are generating huge future liabilities to replace fossil energy infrastructure and pay for climate damages.

US public acceptance of AGW has rebounded to near previous peak - following the warming phase of the enso cycle? http://closup.umich.edu/issues-in-energy-and-environmental-policy/25/acceptance-of-global-warming-among-americans-reaches-highest-level-since-2008/

According to Citicorp reducing GHG is the low cost option. Clicking through to the underlying report provides a wealth of information on energy and climate economics. http://www.theguardian.com/environment/climate-consensus-97-per-cent/2015/aug/31/citi-report-slowing-global-warming-would-save-tens-of-trillions-of-dollars

April 2015 snowpack in the Sierra Nevada was 5% of normal - unprecedented in snowpack record and 500 year tree-ring proxy. http://www.nature.com/articles/nclimate2809.epdf?referrer_access_token=8U88K0Q

That is why they grid the radiosonde data. The radiosonde data lines up very well with the re-analysis data even over short time periods. You wouldn't get such close agreement if the radiosondes were missing important regional temperature trends.

Here is a chart from Christy's upper-air section in the 2014 BAMS state-of-the-climate. He uses RATPAC data and shows that it agrees very well with other upper-air datasets. http://www.ncdc.noaa.gov/bams-state-of-the-climate/