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Topics - sidd

Pages: [1]
1
The forum / Backup
« on: September 19, 2017, 03:11:19 AM »
This site hosts an invaluable collection of links, commentary and original research. I would hate for it to disappear. So I ask if archival sites like the web archive have reasonably complete copies in event of disaster?

I dont know traffic volumes or disk usage for this site, but if disk is no more than a terabyte or so i might be willing to run a static mirror.

sidd

2
The rest / Russia in Ukraine
« on: September 18, 2017, 08:23:31 AM »
I created a thread about western support for nazis in ukraine and some commenters pointed out russia's role. Since I want to keep that discussion focusse, here is a different thread. I'll kick it off with my statement in the Russiagate thread that "Russia considers Ukraine central to Russian interest."

Have at it.

sidd

4
The rest / Economic Inequality
« on: August 23, 2017, 02:32:25 AM »
I start this thread to discuss economic inequality, and I shall kick it off a paper by Piketty et al.

1) Distributional National Accounts: Methods and Estimates for the United States, Piketty et al. 2017 available at  http://gabriel-zucman.eu/usdina

The paper concentrates on income inequality in the USA, both pre and post tax, including benefits through redistribution. I attach

a) the upper panel of figure 3 showing the share of national income for the bottom 50%
b) the lower panel of fig 3 showing showing real income for the botton 50% flattening in the late 80s and that it has not recovered from the 2008 recession
c) The lower panel of fig 5 share of the national income going to the top 1%, showing steady increase.

sidd

5
The rest / New political party in the USA
« on: May 03, 2017, 12:25:34 AM »

6
Science / Attribution of CO2 climate effects
« on: May 02, 2017, 06:44:00 PM »
I have written about Liang's approach to information flow, and here is an application of the technique to detect link between CO2 and global temperature. Nice paper.

DOI: 10.1038/srep21691

open access. very readable.

sidd

7
Science / ice sheet models
« on: April 25, 2017, 04:34:45 AM »
We don't seem to have a dedicated thread to ice sheet models. Here's one by Mikkelsen et al., I notice Grinsted amopng the authors, one models underestimating mass balance of icesheets since they do not account for variability.

http://www.the-cryosphere-discuss.net/tc-2017-47/

sidd

8
The forum / Closed forum or mailing list
« on: April 17, 2017, 07:25:06 AM »
Prof. Ding is being abused in return for his generous participation on this forum. Is it possible to set up a mailing list here so that a more civilized discussion can continue ? I will do it if necessary, but it would be easier here since all of the (constructive) participants already have accounts here.

sidd

9
Developers Corner / Classifiers for surface imagery
« on: December 13, 2016, 08:18:38 PM »
Chapter by Satir and Berberoglu detail various machine learning techniques for classifying pixels from imagery. This can be applied to sea surface also, and to no imagery satellite products product. I see many applications to the cryosphere. Open access.

http://www.intechopen.com/books/landscape-planning/land-use-cover-classification-techniques-using-optical-remotely-sensed-data-in-landscape-plannin

sidd

10
Greenland and Arctic Circle / Baffin Island, Barnes ice cap
« on: December 01, 2016, 02:05:21 AM »
http://blogs.agu.org/fromaglaciersperspective/2016/11/18/barnes-ice-cap-baffin-island-evident-response-climate-change/

Prof Pelto does his usual superlative job. The meltwater streams are quite amazing.

11
Science / Broadening of Agulhas and other western boundary currents
« on: November 09, 2016, 09:26:36 PM »
I think this is important, but i dont know why i think so. I do know that Agulhas affects AMOC, and perhaps vice versa. Kuroshio and East Australia current are broadening also.

doi:10.1038/nature19853

"These results indicate that intensifying winds may be increasing the eddy kinetic energy of boundary currents, rather than their mean flow. This could act to decrease poleward heat transport and increase cross-frontal exchange of nutrients and pollutants between the coastal ocean and the deep ocean."

Below, EKE is eddy kinetic energy.

  "Our results, together with recent analyses in other western ­boundary currents, suggest that intensifying winds may act to increase the EKE of boundary currents, rather than their mean flow. This ­hypothesis draws parallels with the eddy compensation hypothesis for the Antarctic Circumpolar Current in the Southern Ocean, where eddies appear to dampen the effect of increased wind energy input on the mean flow [Ref. 30.] In essence, while winds tend to accelerate the flow and steepen ­isopycnals, eddies mix laterally across the current to slump the ­isopycnals. Coupling between eddies and the atmosphere has also been shown to influence this frontal balance [Ref. 31.] The implication of ­broadening boundary currents is a more porous divide between the continental shelves and the open ocean, leading to greater mixing and cross-frontal exchange. In the Agulhas Current, these changes could also enhance upwelling over the shelf, since the strongest upwelling events are driven by meanders. These implications are in contrast to those of an intensifying flow, which would tend to dampen cross-­frontal mixing and increase meridional heat transport.

  If western boundary currents are not strengthening, observed patterns of surface warming [Ref. 5,9,10] must be explained by a poleward shift of the ocean gyres."

sidd

12
Developers Corner / opportunistic image acquisition
« on: November 05, 2016, 04:27:36 AM »
This is a nice paper on what can be done with consumer grade hardware, and some nice software.
Go-pro camera, Garmin GPS attached to aircraft but I am thinking also of similar drone application.  Open access.

doi:10.5194/tc-2016-228

sidd

13
Science / AMOC slowdown
« on: October 06, 2016, 05:44:51 AM »
Kelly et al. trace AMOC slowdown to Agulhas leakage.

doi:10.1002/2016GL069789

No role for salinity,  AMOC slowdown not due to freshening in the north, rather they see increased salinity from precipitation decrease. This is a new development, Ruth Curry saw the opposite earlier.

14
The forum / https broken [update: should be fixed, too]
« on: June 30, 2016, 06:10:20 AM »
i am having great difficulty accessing https versions of pages. some work, some dont until i try the http version. This reply page for example and many others. Please advise.

sidd

15
Science / Precipitation trends
« on: May 09, 2016, 11:59:27 PM »
We expect increase in precip intensity due to anthro climate change. An Australia-wide study sees storms shrinking in both area and duration together with increases in peak rainfall rate.

doi:  10.1002/2016GL068509

A previous study by some of the same authors is at

DOI: 10.1038/NGEO2456

This will stress stormwater systems leading to more frequent flooding, an especial concern to coastal and floodplain infrastructure. Weather models are not (yet ?) good enuf to model these effects, and i doubt they will improve very quickly.

16
Developers Corner / stop emojis
« on: April 01, 2016, 06:11:59 AM »
i discovered recently that an 8 followed by a closing brace was rendered as an emoji

thus with a space between the 8 and the )

Fig. 8 )

is fine, but with no space

Fig. 8)

wears sunglasses

how to not do this or is this unpossible ?

17
Consequences / Qué se ficieron ?
« on: February 19, 2016, 06:19:22 AM »
I just read the post in the "Coal" thread of yet another coal company ducking out on pension, healthcare and cleanup, while rewarding those most responsible. Those will escape justice for the most part, but ought not to be forgotten. I nominate Don Blakenship as someone to keep track of. Feel free to add others.

Their victims ought not be forgotten either

https://en.wikipedia.org/wiki/Aberfan_disaster

"Wo sind die Tränen von gestern abend?"

Someday, another Zinn will write a people's history of climate genocide.

sidd

18
Policy and solutions / Climate Debt and Credit
« on: September 10, 2015, 05:34:59 AM »
Matthews, 2015 DOI:10.1038/NCLIMATE2774 on national carbon debts and credits

“This Letter presents a new way to quantify historical inequalities among nations using carbon and climate debts, defined as the amount by which national climate contributions have exceeded a hypothetical equal per-capita share over time.”

The largest creditors are India (-75.6,-141.5), Indonesia(-14.2,-27.6), Bangladesh(-12.8,-21.4). The largest debtors are US(100.3,202.7), Russia(27,64.7) and Japan(15.9,25.3). The numbers are in gigatonne CO2 since 1990 and 1960.

In the supplementary, they look at consumption based estimate, which helps China quite a bit. Fig S3.

I attach part of Fig2 and fig S3

sidd

19
The forum / threading
« on: April 18, 2015, 08:17:46 PM »
Can replies be tagged with a reference to the post to which they are a reply ? this reference could be NULL if there is no parent post ? (I have, of course, Usenet threading in mind ...)

sidd

21
The forum / SSL vulnerability
« on: April 10, 2014, 05:38:20 AM »
I am sure the administrators have fixed this ? But it would be nice to have an assurance. Logs should show if it was exploited, perhaps ?

sidd

22
The forum / odd bug or feature on relogin
« on: November 23, 2013, 05:27:44 AM »
First let me say i really like the simplemachines software and will buy the developers a beer or a case if i am in their general vicinity.

as to the odd bug or feature

0)when having more than one browser tab open on this site,
1)having your login time expire before
2)you click on the links from a page that you accessed when already logged in
3)and open them in new tabs
4)and you relogin from one of the tabs

does Strange Stuff as in

5)the tab no longer displays the page you were viewing before you relogged in, but in my case went back to a copy of another open tab (i only had 2 tabs open at the time ...)

(but perhaps it is meant to, to guard against authentication information leaking into unauthenticated tabs ... a Feature, not a Bug ... mebbe like nethack, they thought of everything ...)

sidd

23
The forum / killfiles
« on: July 18, 2013, 07:59:41 PM »
Is the an "ignore poster" capability on this forum, which enables one to eliminate posts by one or more posters being displayed ? Sorta like the Usenet killfile idea.

sidd

24
Antarctica / West Antarctic Divide Core
« on: May 25, 2013, 08:30:33 AM »
Severinghaus at Byrd Polar Research



1 hour fourteen minute
worth the time.

sudd

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