31 January 2013

Sea level's climate time scale

My 'reality-based decision making' post prompted a comment asking for my thoughts about sea level rise, which is more than sufficient excuse to turn to that.  An additional excuse is that it provides a chance to look at how to decide climate time scales for something other than temperatures.  For global mean temperature trends, I found that you need 20-30 years to determine a climate trend.  We'll see that it is 40-60 years, 60 for preference, for sea level.

My starting point for data was the University of Colorado sea level group.  They provide satellite data back to late 1992.  High quality data, but only for a short period of time.  If global sea level's time scales are like global mean temperature's, then it's only just gotten long enough to provide a climate number.  Fortunately they list links to other sea level groups, including the Permanent Service for Mean Sea Level.  They have three global reconstructions available.  I'll take this one -- published in the scientific literature as: Recent global sea level acceleration started over 200 years ago?", Jevrejeva, S., J. C. Moore, A. Grinsted, and P. L. Woodworth (2008), Geophys. Res. Lett., 35, L08715, doi:10.1029/2008GL033611 -- on the grounds that it covers the longest time period and has the most recent literature publication date.  It will be a good project for a reader to see if the conclusions here change, and how, if you use one of the others instead.

11 January 2013

Looking back at blogs 1

Some of these might still be active, at least the author might be.  Please let me know the new locations if I don't have one.  If not, well, they still wrote some articles worth consideration.

Trees for the Forest
Rust Never Sleeps

Old Man in a Cave


Rationally Thinking Out Loud (new location) http://rationallythinkingoutloud.wordpress.com/ -- old location

Respectful Insolence -- The blog certainly has continued, this is the link to the new feed location.  But some good older articles on science, in particular medicine, vs. nonscience.

The Questionable Authority Old location: http://scienceblogs.com/authority/, New location: The Questionable Authority

The Middle Way (low volume, more philosophical, blog, by a friend)

Vickie's Prostitution Blog (my wife)

10 January 2013

Bits from 2012

Some items that interested me in 2012 that I never made full posts from ...

As you've no doubt heard, the 5th review from IPCC is in progress.  I passed up yet another opportunity to be an expert reviewer.

One method of getting science together is a special issue or theme issue of a scientific journal.  One that crossed my desk and I thought might be interesting to blog readers are:
  • Call for Papers – Climate Consensus: Steps Toward a Global Understanding of Climate
And, of course, educational meetings/workshops/'summer school':
  • European Earth System and Climate Modelling School sponsored by ENES
A major method (with much advertising, hence the longer list) is scientific meetings.  It sometimes seems like people think there are only 5-10 scientists in the world, or at least in any given area.  Below are some sessions at meetings from 2012.  Each session probably has something like 100 people present (anywhere from 30-300).

09 January 2013

Happy New Year 2013

Happy near year! 

I see that I have been away from here for quite a while, including past a spectacular (again) new minimum in Arctic sea ice extent this past September.  Certainly lost me at least one of my bets with Alastair, maybe both.  I'll be looking in to it and write up a full evaluation of the predictions I worked with.

One of the reasons for the quiet here is that I've been working on articles for professional journals.  2 now out in Deep Sea Research, 1 to be appearing in Ocean Modeling, 1 already in review at Weather and Forecasting.  And two in pre-submission review, one for Climate Dynamics and another for Weather and Forecasting.  4 more in progress towards the internal review stage -- one a technical note on what I've been doing the last 15 years for sea ice concentration analysis, two for the Journal of Climate, and one for sea ice modeling.  Not sure where/how I'll be publishing that.  Somehow the brain cells for writing get fatigued, so if I'm writing much at work, I don't do so much here.  The exercise is starting to pay off, though, so they seem to feel like they can do both now.

Good news in the background is that I'll be producing better plots when I do start more regular posting here.  Had to bite some bullets to get figured out how to make publishable plots for the journals.  More of an issue than it should have been.  But now resolved well enough, with the side benefit that it also lets me make better plots for blogging.