My web presence

Showing posts with label climate. Show all posts
Showing posts with label climate. Show all posts

Monday, 4 April 2016

Another Take on Climate Change, Part VI (the last)


previously asked  how current vagaries of climate may relate to earth's magnetic field reversals? One problem was that geological records (ocean bottom magnetic stripes) didn't span well into historic records (volcanic lava deposits)! Well this appears to have been addressed in this video:

Wednesday, 20 January 2016

Another Take on Climate Change, Part V

[Update: Part VI, more on geomagnetic reversals]

Parts I, II, III & IV from March 2011 became relevant in a comment yesterday on Euan Mearns post on extreme climate. He pointed to the Laschamp event, and suggests this: that the wandering of the North Pole heralds a impending magnetic reversal, such as happened 4000 years ago evidenced in the French Massif Central near Clermont Ferrand.

Sunday, 23 November 2014

Web Maps on Steroids, Part II

I showed a couple of months ago ways to post mega-datasets online without choking the system. This month OSGeoUK gave me the opportunity to present the same on PostGIS Day 2014, as postGIS was the backbone of two of these examples on GIScloud and GeoCloud2. Thanks to OSGeoUK and British Computer Society for hosting this.

Saturday, 27 September 2014

Web maps on steroids

The last 6 blog posts over the last 3 months chronicled the use of dynamic maps using time attribute - years for historic ship tracks and wind data from same 150-350 yrs ago - not to animate maps but to filter them by decade and manage data fetches on ArcGIS Online. A parallel series of posts showed mega data sets on Amazon Web Services, as Mapcentia assured me postGIS handled giga datasets...

Sunday, 23 February 2014

Global Sailings (1662 - 1856, English, Spanish, Dutch, French) revisited

[Update: climate data (wind speed & direction) have now been added in short & long posts]

I originally extracted CLIWOC (CLImatological database for the World's OCeans) ship captains' logs ships locations over a decade ago, to demonstrate the processing of 250K+ points in ArcGIS desktop using then new File Geodatabase. Five years later I posted this on my old website with instructions how to use it in  old ArcGIS Explorer and KML, and then I put a layer package on arcgis.com - both related historic details like de laPerouse's demise below, the importance of data standards and metadata, and the interst it generated elsewhere - more recently I posted a time-based variation of same, where using a time slider helps clarifiy complex data on desktop GIS.

Wednesday, 31 October 2012

Step through Hurricane Sandy the last six days


NOAA NRT AIRS fly satellites that record cloud cover and other atmospheric sensors described when I tracked Kuwaiti sandstorms. Stepping back six days offers a fascinating glimpse in the progress of the hurricane. Hurry as this posting will quickly become stale-dated as the storm moves off the US East Coast. Here is a presentation built in ArcGIS Online for your viewing pleasure.

Thursday, 31 March 2011

Another Take on Climate Change, Part IV

[Update: Part V, more on polar wanderings]

From guardian.co.uk today: Goce satellite maps the Earth's gravity in unprecedented precision. Aside from updating on Part III of this series, this slots right into my comment on the lesser-know fact that the earth wobbles on it axis, and that mass plate-tectonic movements are the result as well as the cause of earth tremors along plate boundaries

Friday, 11 March 2011

Another Take on Climate Change, Part II

[Update 2: thanks Greg Cocks for this April 2019 update
Update 1: Part III, more on plate boundary earthquakes]

A year ago today I posted here on the Chilean 8.8 magnitude earthquake.... The recent earhtquakes and tsunamis in Japan and New Zealand, and China and Indonesia before that, truly indicate an increased rate of incidence in these catastrophies! Add to that the more frequent hurricanes and cyclones off the Gulf of Mexico and NE Australia, and fires or floods in N America, Australia and Europe, and we truly wonder what is going on really?

Saturday, 13 March 2010

Another take on climate change

[ 2021 update: full twitter thread why "plume push" theory may be flawed
  2010 update: See follow-on Part II here ]

If the 8.8 magnitude Chilean quake may have shortened days by an infenitisimal amount late last month, it highlights the lesser-know fact that the earth wobbles on it axis, and that mass plate-tectonic movements are the result as well as the cause of earth tremors along plate boundaries below (may need to install Google Earth plug-in as indicated).

Wednesday, 30 December 2009

Webmaps, history, climate and geology

Chatting with local history buffs brought up amazing facts about climate change and sea level rise since the Middle Ages in East Anglia. One book's sketch map relates how the North Sea coastline differed from today, and how that affected Anglo-Saxon socio-economics there before and after the Norman conquest and the Domesday book.