Comments on: Peterson (2003)

By: Trends in Peterson 2003 « Climate Audit

Trends in Peterson 2003 « Climate Audit — Wed, 31 Mar 2010 16:49:53 +0000

[...] posts are here and [...]

By: Peterson’s “Urban” Sites « Climate Audit

Peterson’s “Urban” Sites « Climate Audit — Wed, 31 Mar 2010 16:49:47 +0000

[...] that the difference between “urban” and rural sites was negligible. (See related posts here and [...]

By: David Smith

David Smith — Sun, 14 Dec 2008 22:42:07 +0000

Here’s the December 11, 2008 UHI map for Houston, at dawn. The green dot is the official weather station, which I estimate experienced a UHI effect of 2 or 3F. The maximum UHI effect in the metropolitan area appeared to be 6 to 8 F.

By: STAFFAN LINDSTROEM

STAFFAN LINDSTROEM — Tue, 13 May 2008 15:20:01 +0000

David … addendum Just checked from memory, Alunda, a smaller
main road thermometer logged -21C on …Oct 23, 2003, about
21:30 in the evening! Uppsala AP just a couple of kilometers
outside Uppsala did not measure lower than -12.3C! On March 2,
2005 Uppsala AP had -32.6C…AND ALUNDA, 35 km NE of Uppsala,
yes, remains to be investigated… BTW Car, auto aka MHI (Mobile
Heat Island…)

By: STAFFAN LINDSTROEM

STAFFAN LINDSTROEM — Tue, 13 May 2008 14:58:13 +0000

David Smith…I would like too see road temp readings from roads
with as little traffic as possible. How does Texas road administration
function?? Best Staffan (Still alive in spite of 16C drop in
temperatures in 20 HOURS…Sweden is NOT South Dakota you know…!)

By: David Smith

David Smith — Tue, 13 May 2008 02:24:08 +0000

A temperature map of Dallas / Fort Worth TX US is here

The purple isotherms are 2F apart.

The temperatures are averages of nearby personal weather stations.

The main airport is near the “o” in “Worth”.

It’s a rather distinct heat island even though the weather conditions weren’t ideal.

By: Jeff C.

Jeff C. — Thu, 08 May 2008 19:55:05 +0000

jc – you are right regarding Tucson. Unfortunately, OK City doesn’t seem to have many personal weather stations.

Here is another potential good one – Columbus, Ohio. Lots of personal weather stations, middle of nowhere, flat terrain.

http://www.wunderground.com/stationmaps/gmap.asp?lat=39.99922&lon=-83.00995&zoom=10&type=ter&rad=0&wxsn=1&wxsn.mode=tw&svr=0&cams=0&sat=0

By: David Smith

David Smith — Thu, 08 May 2008 19:11:40 +0000

jc, I agree – Houston has a lot of drawbacks. For me it has the advantage of being my backyard while I try to develop an approach. What do you think about Kansas City or Tulsa as additional possibilities?

By: jc-at-play

jc-at-play — Thu, 08 May 2008 18:20:56 +0000

Re #41 David Smith – In hindsight, it was a mistake for me to say that the changes in elevation are “significant”, but they are somewhat greater than your description. Looking at http://nmviewogc.cr.usgs.gov/viewer.htm, I find for example that Conroe has an elevation of 166 feet, compared to central Houston’s elevation of about 50 feet. However, the observed temperature difference between Conroe and central Houston was about ten degrees, which clearly is far too large a change to be accounted for solely by the relatively small change in elevation.

The point I was trying to muddle towards was expressed very well by Jeff C – rather than looking at Houston, it would be better to look at cities with minimal influence from topography, elevation, or influences from adjacent bodies of water.

[Side remark to Jeff C: There are 7000 foot peaks within 20 miles of Tucson, so it would appear not to be a particularly good candidate. Indianapolis and Oklahoma City, however, seem to be first-rate.]

By: David Smith

David Smith — Thu, 08 May 2008 03:12:45 +0000

Re #39 jc, those of us in the Houston area, like Leif, would probably welcome some elevation change. I'm afraid that midcity is about 50 feet ASL while fifty miles to the northeast the elevation only approaches 100 feet ASL. Not much elevation change in this region. Re #40 Jeff, I agree about the potential value of the huge amount of personal weather station data. I'm optimistic that, with caution, we may be able to learn some things. There may be a guest post at Anthony Watts site regarding personal weather station "clusters" (personal stations in close proximity to one another which likely differ only in microsite factors like nearby trees and concrete). An example of the temperatures in such a cluster is here , where the temperatures stay close to one another until microsite effects kick in during daylight. On a cloudy night those lines stay quite close to one another. On a clear, low-humidity night (not shown) they spread apart, again apparently due to microsite effects.