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Topics - RaenorShine

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1
Greenland and Arctic Circle / Greenland 2015 Melt Season
« on: April 12, 2015, 05:37:37 PM »
NSIDC have bought up their Greenland Today site for this season (hat tip to Andy from San Diego on robertscribblers blog for pointing this out!), and that is when I've started this thread for the past couple of years.

As previous years I'll be posting regular comments on Melt Area (calculated from satellite measurements by NSIDC http://nsidc.org/greenland-today/) and Surface Mass Balance (calculated by a DMI model and reported on Polar Portal http://polarportal.dk/en/groenlands-indlandsis/nbsp/isens-overflade/ and DMI's own site http://www.dmi.dk/en/groenland/maalinger/greenland-ice-sheet-surface-mass-budget/).

The melt season proper will not really start until the middle of May, but we may start seeing the early signs shortly.

A couple of things of note from over the winter.

The statistical relationship between ice sheet reflectivity and total melt loss broke down in 2013 according to this release from DMI http://polarportal.dk/en/nyheder/arkiv/nyheder/ice-sheet-surprises/. Daily albedo images (from satellite data) are reported on the Polar Portal, but they will not be using this to estimate total loss (that is Surface Mass Balance and Glacial Runoff), but instead  this will only be reported on a 3 month+ delay in GRACE Data.

Both Polar Portal and NSIDC have issued a summary of the 2014 melt season
The winter of 2014/2015 has added a lot more Surface Mass Balance than average (although we seem to be gradually returning to mean.http://polarportal.dk/fileadmin/polarportal/surface/SMB_curves_LA_EN_20150411.png. What is striking is that this is almost all on the Southern tip and East coast of Greenland, with the North and West of Greenland significantly below average. http://polarportal.dk/fileadmin/polarportal/surface/SMB_map_LA_acc_EN_20150411.png.

With El Nino providing record tempuratures and sea ice at a very low level we should be in for another interesting melt season.

2
Consequences / North Atlantic Ocean Currents
« on: March 23, 2015, 06:45:38 PM »
Just found what looks to be a major new paper in nature climate change showing slow down in the Atlantic meridional overturning circulation (AMOC, also known as the gult stream etc), and also showing thisis unprecedented in the last 1000 years.

The paper is paywalled, but there is already several blog posts in what looks to be a coordinated release

http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate2554.html
Quote
Exceptional twentieth-century slowdown in Atlantic Ocean overturning circulation
Stefan Rahmstorf,    Jason E. Box, Georg Feulner,   
    Michael E. Mann, Alexander Robinson,    Scott Rutherford & Erik J. Schaffernicht


Possible changes in Atlantic meridional overturning circulation (AMOC) provide a key source of uncertainty regarding future climate change. Maps of temperature trends over the twentieth century show a conspicuous region of cooling in the northern Atlantic. Here we present multiple lines of evidence suggesting that this cooling may be due to a reduction in the AMOC over the twentieth century and particularly after 1970. Since 1990 the AMOC seems to have partly recovered. This time evolution is consistently suggested by an AMOC index based on sea surface temperatures, by the hemispheric temperature difference, by coral-based proxies and by oceanic measurements. We discuss a possible contribution of the melting of the Greenland Ice Sheet to the slowdown. Using a multi-proxy temperature reconstruction for the AMOC index suggests that the AMOC weakness after 1975 is an unprecedented event in the past millennium (p > 0.99). Further melting of Greenland in the coming decades could contribute to further weakening of the AMOC.
Stefan Rahmstorf has posted this to Real Climate
http://www.realclimate.org/index.php/archives/2015/03/whats-going-on-in-the-north-atlantic/

Video Interviews and commentery by Peter Sinclair



http://climatecrocks.com/2015/03/23/a-nasty-surprise-in-the-greenhouse-new-paper-new-video/

(added direct link to youtube interviews)
PS please move to another section if needed Neven, wasn't sure where this belongs!

3
Possible volcanic eruption under a glacier in Iceland .....

http://www.theguardian.com/world/2014/aug/18/iceland-volcano-risk-raised-to-orange


Quote
Bardarbunga is Iceland's largest volcanic system, located under the ice cap of the Vatnajokull glacier in the southwest of Iceland. It is in a different range to Eyjafjallajokull.

And there is really a huge earthquake storm at the moment.  Iceland met office monitor earthquakes on the following link. http://en.vedur.is/earthquakes-and-volcanism/earthquakes/

This could get interesting for air travel in Europe if winds are in the right direction.

4
Prof. Marco Tedesco's site http://www.greenlandmelting.com/ has been quiet for a couple of years, but there have been a couple of postings recently on several papers which have already been discussed here.  one that hasn't as far as I know is below, and the full paper is freely available at Nature.

It identifies a possible negative feedback as a result of increased run off from Greenland/Antarctic, which is as a source of iron.  Iron being dumped into the ocean as a form of geoengineering has been thought of as a possible sink as it increases algal blooms.  I've copied the link and abstract below, which links to the full paper.

http://www.nature.com/ncomms/2014/140521/ncomms4929/full/ncomms4929.html

Quote
Ice sheets as a significant source of highly reactive nanoparticulate iron to the oceans
Jon R. Hawkings, Jemma L. Wadham, Martyn Tranter, Rob Raiswell, Liane G. Benning, Peter J. Statham, Andrew Tedstone, Peter Nienow, Katherine Lee & Jon Telling

The Greenland and Antarctic Ice Sheets cover ~\n10% of global land surface, but are rarely considered as active components of the global iron cycle. The ocean waters around both ice sheets harbour highly productive coastal ecosystems, many of which are iron limited. Measurements of iron concentrations in subglacial runoff from a large Greenland Ice Sheet catchment reveal the potential for globally significant export of labile iron fractions to the near-coastal euphotic zone. We estimate that the flux of bioavailable iron associated with glacial runoff is 0.40–2.54 Tg per year in Greenland and 0.06–0.17 Tg per year in Antarctica. Iron fluxes are dominated by a highly reactive and potentially bioavailable nanoparticulate suspended sediment fraction, similar to that identified in Antarctic icebergs. Estimates of labile iron fluxes in meltwater are comparable with aeolian dust fluxes to the oceans surrounding Greenland and Antarctica, and are similarly expected to increase in a warming climate with enhanced melting.


5
Just heard this on BBC radio news ......

http://www.bbc.co.uk/news/science-environment-27465050

Quote
Antarctica is now losing about 160 billion tonnes of ice a year to the ocean - twice as much as when the continent was last surveyed.

The new assessment comes from Europe's Cryosat satellite, which has a radar instrument specifically designed to measure the shape of the ice sheet.

The melt loss from the White Continent is sufficient to push up global sea levels by around 0.43mm per year.

Scientists report the data in the journal Geophysical Research Letters.http://onlinelibrary.wiley.com/doi/10.1002/2014GL060111/abstract

Anyone getting Climate Bad News Fatigue yet? ;p

6
Greenland and Arctic Circle / Greenland 2014 Melt Season
« on: May 04, 2014, 12:02:11 PM »
As we are now in March I thought I'd start us a Greenland Melt Thread for what will be another interesting season.  I've listed a couple of resources below I followed last year.  Any other suggestions greatly received!

NSIDC have put up the first picture of the season (for May 1) after their calibration http://nsidc.org/greenland-today/, and also reanalyzed the year to date, with a small blip in surface melt already in late April.

Meanwhile, DMI http://www.dmi.dk/en/groenland/maalinger/greenland-ice-sheet-surface-mass-budget/ is showing melting in the SW of Greenland. The overall surface mass balance on their site is following the average growth.  DMI also have a good record of satellite images around the edge of Greenland. http://ocean.dmi.dk/arctic/kangerlussuaq.uk.php

Polar portal http://polarportal.dk/en/greenland-ice-shelf/nbsp/total-mass-change/ have not yet started plotting for 2014 for total mass change, but this year could be interesting to say the least.  Even with the cold year in 2013, the total mass loss was still above the average since 2000.

7
from the BBC's Summary of the budget http://www.bbc.co.uk/news/uk-politics-26626280

Quote
All long-haul flights to carry lower rate of air duty currently charged on flights to US

Fuel duty rise planned for September will not happen

£7bn package to cut energy bills, including £18 per ton cap on carbon price support, predicted to save medium-sized manufacturers £50,000 and families £15 a year

£140m extra for flood defence repairs and maintenance

How are we supposed to meet our current mediocre targets for carbon while cutting taxes on pollution etc?

An extra GBP140m to repair the damage already encountered isn't going to stop the dam from bursting in the next severe weather event when you are still cutting capital spending on new defences!

8
Just seen this article on BBC News.

http://www.bbc.co.uk/news/science-environment-26455763

Quote
The world's financial markets could be creating a "carbon bubble" by over valuing the fossil fuel assets of large companies say MPs.

The problem is that when if we actually start to take mitigation seriously at some point we are going to have to leave known carbon deposits in the ground.  Oil, Gas and Coal companies currently count their discoveries as assets which they can exploit for profit at a later date.  If they can't be exploited due to environmental legislation, they become worthless as assets, and the companies have to write off hefty losses on their assets, which could then cause the company to go bancrupt if they have borrowed against that asset.

I'd say that the bubble would already be here if we were serious about mitigation, but the fact that they are discussing a future bubble shows that we are not yet there despite the increasing greenwashing.

9
Policy and solutions / Consumer Techology and the Internet
« on: February 26, 2014, 04:08:31 PM »
Came across this interesting piece on BBC news. It covers the market from a economic standpoint but is damning of it for a mainstream news site.

http://www.bbc.co.uk/news/business-26336736

It's a really well argued piece about the current state of the technology market

a couple of quotes

Quote
Beware of the belief that the technology curve is an inevitable advance for good. More and more economic activity is now derived from things that simply do not matter. Futility beckons.

Quote
Historians tells us that one of the contributory factors to the decline and fall of the Roman Empire was the crippling expense of the state-organised circuses that distracted the populace from the tiresome realities of life in Rome.

I wonder whether we are now embarked on a similar trajectory, in our new futile economy.

The internet has changed a lot from its roots as a communications tool for scientists and academics (and of course the US Govt) to the mass entertainment and communication network it has become today.

From the environmental standpoint it's definately been a double edged sword.  Physical media sales (CD/DVD/Books/Newspapers etc) are all falling though the floor, and consuming these items on tablets etc can save resources (http://www.slate.com/articles/health_and_science/the_green_lantern/2010/08/should_you_ditch_your_books_for_an_ereader.html) But, we also upgrade our technology far too frequently due to built in obsolescence and our desire for the next big thing (can you really warrant an upgrade from an old working smartphone or tablet to a newer model based on functionality alone?)

Content and Video on the Web is also increasing hugely in quality and therefore bandwidth, with 4K and beyond around the corner. I dread to think how long most of the web takes to load on a non broadband connection nowadays.  All of this could politely be called 'nice to have' at best and a complete waste of resources at worst.

As Neven said on the Global Economics thread the internet has become an essential for most of us now (me included). Could the internet be good (or at least neutral) for the environment in the long term, possibly, but on the course we are going on with it I doubt it.

10
The forum / ASIB downloading multiple files warning in Chrome
« on: September 23, 2013, 12:12:49 PM »
Neven,

Just started receiving warnings on the blog saying that it is downloading multiple files in Chrome.

It downloads 'widgets-tweet_button.html.torrent' and warns of others.  The tweet buttons are not showing but are in Internet Explorer.

Not sure if this has just been added, but wasn't receiving errors before.

Cheers

11
BBC article on the summit outcome

http://www.bbc.co.uk/news/science-environment-22959578

Quote
The UK's recent run of damp summers could be down to a cyclical warming of the Atlantic Ocean.

Quote
Explaining the cold winters of 2010/11 and this past spring were more of a challenge, said the scientists. Dr James Screen from the University of Exeter said that a more complicated basket of factors was involved.

"The cycle we've been talking about in the north Atlantic seems to be more important for controlling summer weather in the UK, our current understanding of the role of Arctic sea ice is that it is more important in controlling winter weather."

So the message seems to be we think things will return to normal .......

12
Greenland and Arctic Circle / Early 2013 Melt in SE Greenland?
« on: February 23, 2013, 06:00:16 PM »
I've been following the early season in Greenland on the new NSIDC site http://nsidc.org/greenland-today/ and have seen that there is early melt in the SW of Greenland over the past month or so.

However, according to Denmarks Meteorology Institute, the daily mass change in the ice sheet has been positive in this area for the past couple of days in the same area that NSIDC shows melting(http://www.dmi.dk/dmi/index/gronland/indlandsisens_massebalance.htm in danish).

Both sites use different measurements (NSIDC uses a satellite survey, DMI uses a model based on the weather to estimate mass change).

Looking at the weather in that area on Wunderground (http://www.wunderground.com/cgi-bin/findweather/getForecast?query=65.58000183,-37.15000153&sp=BGKK it looks to have been slightly above freezing during the day, and raining at times.

My question as a non scientist  (and a climate/ice newbie) is what is actually happening in the area?  I know that any ice melt and rain during the day will probably refreeze overnight at the moment, giving mass gain.

Also, could the rain be giving a false positive on the satellite survey (i.e. the rain leads to water on the surface of the ice, leading to a 'melt' reading)?



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