| Chronology | Current Month | Current Thread | Current Date |
| [Year List] [Month List (current year)] | [Date Index] [Thread Index] | [Thread Prev] [Thread Next] | [Date Prev] [Date Next] |
----------------------------------------------------------------------
Message: 1
Date: Sat, 04 Apr 2009 13:06:32 -0500
From: Brian Whatcott <betwys1@sbcglobal.net>
Subject: Re: [Phys-l] global temperatures
To: marx@phy.ilstu.edu, Forum for Physics Educators
<phys-l@carnot.physics.buffalo.edu>
Message-ID: <49D7A1A8.4070901@sbcglobal.net>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
It's interesting to estimate the thermal time constant of the Earth.
This would be
an important underlying trend line effect resulting from any significant
change of solar heating.
As I recall, Kelvin did such an estimate, neglecting the effect of
nuclear internal heating.
His estimate for the Earth's age amounted to a small number of million
years, for it to cool to the present ambient.
I imagine that would place the terrestrial TTC at perhaps 200 kyr about....
I ask myself: if the Earth acted like a homogeneous body with a thermal
time constant of 200 kyr, and there was a step increase of say 5% in
solar heating: then after ten years, what would be the expected increase
in mean World temperature from say 4K through 288K? Maybe (288K- 4K) *
5% * 10/200000 = 0.7 milliK
We seem to be dealing with some change of rather larger magnitude. Then
again, the
lowest 30,000 ft of atmosphere, and highest 1000 feet of Earth - ground
and sea are far from a uniform passive material.
Brian W
marx@phy.ilstu.edu wrote:
Rick and others,
There has been a flattening and perhaps a slight decline in global temperatures, depending on the
dataset you look at. One could draw the conclusion that there is not a direct connection between
increased CO2 and global temperatures or that there are more parameters that need to be considered.
The modelers claim that the influence of the Sun is minimal. However, it is curious that the flattening
and slight decrease are coming at a time when solar activity is at a century minimum.
In the late 90s and first few years of this decade, solar activity was at a long term high...
http://news.bbc.co.uk/2/hi/science/nature/3869753.stm
Check out the report from NASA this week...
http://science.nasa.gov/headlines/y2009/01apr_deepsolarminimum.htm
On 16 Mar 2009 at 14:43, Rick Tarara wrote:
I noticed nobody has answered Bob's question about global temps over the
last ten years. I'm sure he knows, but I actually didn't. So I Googled
'Global Temperature by year'. I would suggest two quick looks....
www.boston.com/bostonglobe/editorial_opinion/oped/articles/2008/01/06/br_r_r_where_did_global_warming_go/
This one gives a typical newspaper (and GW skeptic) account, but
http://www.cru.uea.ac.uk/cru/info/warming/
is not from a skeptic and has an informative graph.
The bottom line is that the temp hasn't really changed in the past 10
years--it has been high, but that is the predominant trend that has been
clear for some time now. If anything the trend looks to be turning some
(but too little data to be sure). Now this flattening is during a time of a
4% CO-2 increase, but what is interesting to me is that the rate of increase
from 1975 to 2000 is about the same as it was between 1915 and 1940, when
the CO-2 concentrations weren't nearly what they were at the end of the 20th
Century.
These are, IMO, the types of data that should trigger some caution, at least
some healthy skepticism concerning the model predictions. Again, this is
just SO complicated. Is the leveling because of increased aerosols and
Global dimming -- or is the global air quality better than earlier which
makes a ten year leveling more mysterious? What about the other natural
drivers--the sun for example. What's it been doing during this ten year
period--has it cooled off enough to compensate for the greenhouse increases
or is it pumping in more energy such that we would have expected continuing
record setting temps (1998 is still the hottest--according to the graph and
the Boston Globe story). I would point to the last paragraph of the Globe
story! ;-)
Rick
***************************
Richard W. Tarara
------------------------------
Message: 2
Date: Sat, 04 Apr 2009 12:32:24 -0700
From: John Denker <jsd@av8n.com>
Subject: Re: [Phys-l] global temperatures
To: Forum for Physics Educators <phys-l@carnot.physics.buffalo.edu>
Message-ID: <49D7B5C8.6020204@av8n.com>
Content-Type: text/plain; charset=UTF-8
On 04/04/2009 08:02 AM, Rick Tarara wrote in part:
We need to keep the questions clear here. The polar melting (and there has
been some controversy on that lately as well), [1]
Controversy? There's also controversy about evolution, and controversy
about whether astronauts landed on the moon, and controversy about
whether Elvis is dead. Controversy is not evidence. Please let's
stick to the evidence.
See also
http://www.reuters.com/article/latestCrisis/idUSN03361051
the last 10 years when the global temperature has not increased. [2]
How do you know that? Just because Michael Crichton said so
doesn't make it so.
This is an interesting bit of spin: Take a point [1] that is well
supported by the evidence and say it is controversial ... and then
take a point [2] that is not supported by the evidence and blurt
it out as if it were a God-given fact. Most people on this list
are not fooled by this sort of spin. The facts are not changed by
this sort of spin.
In science we learn to deal with data that has fluctuations. The
fluctuations in the temperature record are such that over any 10
year period ?T/?t is not a reliable estimate of the actual trend.
More careful analysis is required ... maybe something as "sophisticated"
as the curve-fitting that is taught in introductory physics courses.
If you take a 5-year moving average, so as to get rid of the worst
of the fluctuations, the point for 2008 is markedly higher than the
point for 1998.
http://data.giss.nasa.gov/gistemp/graphs/Fig.A2.lrg.gif
Yes, you can find wiggles on top of the trend. But the trend is
still there.
None of these questions should be taken as nay-saying or blind skepticism,
rather (I think) legitimate questions about the MODELS which we are (forced)
to use for future planning. All data, including a decade long pause in
temperature increases, are tests for these models. How well do they
accommodate such data?
Twenty years ago, Hansen et al. used their model to make predictions.
The model's 20-year prediction "accommodates" current data reasonably
well.
http://pubs.giss.nasa.gov/abstracts/2006/Hansen_etal_1.html
You can find stretches where the data is below the trend for two or
three years at a time, but mostly it just follows the trend. If you
have a model that you think is better, show us the model and explain
why it is better.
There are well-established statistical techniques for validating the
predictive power of such models.
------------------------------
Message: 3
Date: Sat, 4 Apr 2009 17:21:02 -0400
From: "Rick Tarara" <rtarara@saintmarys.edu>
Subject: Re: [Phys-l] global temperatures
To: "Forum for Physics Educators" <phys-l@carnot.physics.buffalo.edu>
Message-ID: <93557E5CE31145DCA06FC9841957F760@rtararapc1>
Content-Type: text/plain; format=flowed; charset="utf-8";
reply-type=original
----- Original Message -----
From: "John Denker" <jsd@av8n.com>
On 04/04/2009 08:02 AM, Rick Tarara wrote in part:
We need to keep the questions clear here. The polar melting (and thereControversy? There's also controversy about evolution, and controversy
has
been some controversy on that lately as well), [1]
about whether astronauts landed on the moon, and controversy about
whether Elvis is dead. Controversy is not evidence. Please let's
stick to the evidence.
The Controversy is exactly over the evidence--just how much of the polar
ice has melted.
But if what one gets on this list are flippant and derogatory
responses......................
rwt
------------------------------
Message: 4
Date: Sat, 4 Apr 2009 14:45:37 -0700
From: John Mallinckrodt <ajm@csupomona.edu>
Subject: Re: [Phys-l] global temperatures
To: Forum for Physics Educators <phys-l@carnot.physics.buffalo.edu>
Message-ID: <B53DE1D8-6D33-468E-9CD3-01E04F5BF605@csupomona.edu>
Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed
Rick,
The only news I've heard recently is that the melting appears to be
occurring much faster than any of the models had predicted, but that
wouldn't seem to constitute a "controversy" in the context of this
discussion. Is that what you are referring to?
John Mallinckrodt
Cal Poly Pomona
On Apr 4, 2009, at 2:21 PM, Rick Tarara wrote:
----- Original Message -----
From: "John Denker" <jsd@av8n.com>
On 04/04/2009 08:02 AM, Rick Tarara wrote in part:The Controversy is exactly over the evidence--just how much of the
We need to keep the questions clear here. The polar melting (andControversy? There's also controversy about evolution, and
there
has
been some controversy on that lately as well), [1]
controversy
about whether astronauts landed on the moon, and controversy about
whether Elvis is dead. Controversy is not evidence. Please let's
stick to the evidence.
polar
ice has melted.
But if what one gets on this list are flippant and derogatory
responses......................
rwt
_______________________________________________
Forum for Physics Educators
Phys-l@carnot.physics.buffalo.edu
https://carnot.physics.buffalo.edu/mailman/listinfo/phys-l
------------------------------
Message: 5
Date: Sat, 04 Apr 2009 16:39:31 -0600
From: "John SOHL" <jsohl@weber.edu>
Subject: Re: [Phys-l] global temperatures
To: "Forum for Physics Educators" <phys-l@carnot.physics.buffalo.edu>
Message-ID: <49D78D44.6268.00E4.0@weber.edu>
Content-Type: text/plain; charset=US-ASCII
What we need to do is get the Triana/DSCOVR mission launched and in place at the L1 point. This mission is designed to monitor the radiation budget for the Sun and Earth and to give some very important information about global climate change. The Bush administration deep sixed the mission for years for no really valid reason as far as I can tell. NASA just tested the spacecraft (it was built years ago and has been sitting in a warehouse waiting for Bush to go away) and it is in good health. The Bush administration had not been willing to publicly announce why they blocked its launch. They also refused to release documents about administrative reviews of the mission. Secrecy is such an aggravating policy and it results in a lot of guess work by others.
A few hundred million dollars to launch this craft would tell us a lot about global climate change. Unfortunately, nearly 8 years of data have been missed because the already completed craft is just sitting idle in a warehouse.
This mission is described a bit at:
http://hsd.gsfc.nasa.gov/news/about_Triana_DSCOVR_Spacecraft_Successfully_Revived_from_Mothballs.html
and
http://en.wikipedia.org/wiki/Deep_Space_Climate_Observatory
Data from this spacecraft could potentially answer a lot of questions about the impact of the Sun on Earth and Earth's climate.
All the best,
John
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
John E. Sohl, Ph.D.
Professor of Physics
Weber State University
2508 University Circle
Ogden, UT 84408-2508
voice: (801) 626-7907, fax: (801) 626-7445
cell: (801) 476-0589
e-mail: jsohl@weber.edu
------------------------------
Message: 6
Date: Sat, 4 Apr 2009 18:48:24 -0400
From: "Richard Tarara" <rbtarara@sprynet.com>
Subject: Re: [Phys-l] global temperatures
To: "Forum for Physics Educators" <phys-l@carnot.physics.buffalo.edu>
Message-ID: <BB8F56D78CB94421B23017C38B00320C@DesktopRick>
Content-Type: text/plain; format=flowed; charset="iso-8859-1";
reply-type=original
No..there was a thread--maybe it was of PhysSoc about how the ice was being
measured--from photos, which don't show thickness. I forget all the details
now, just that there was controversy over how the amount of ice was being
determined. Someone had offered that the ice was 'gone' but that certainly
is not yet the case. Again, the 'controversy' that was being discussed (and
I offered this just as an aside anyway) was over the data
collection--basically how reliable IS the data. My point only being that
even the 'data' in the complex issue is sometimes in question. I see that
John Sohl has just offered a partial solution to the data question, but a
solution still awaiting a launch window. Does this mission require the
Shuttle--if so, it is probably dead. If not, what's the hang up?
Rick
----- Original Message -----
From: "John Mallinckrodt" <ajm@csupomona.edu>
To: "Forum for Physics Educators" <phys-l@carnot.physics.buffalo.edu>
Sent: Saturday, April 04, 2009 5:45 PM
Subject: Re: [Phys-l] global temperatures
Rick,
The only news I've heard recently is that the melting appears to be
occurring much faster than any of the models had predicted, but that
wouldn't seem to constitute a "controversy" in the context of this
discussion. Is that what you are referring to?
John Mallinckrodt
Cal Poly Pomona
On Apr 4, 2009, at 2:21 PM, Rick Tarara wrote:
----- Original Message -----_______________________________________________
From: "John Denker" <jsd@av8n.com>
On 04/04/2009 08:02 AM, Rick Tarara wrote in part:The Controversy is exactly over the evidence--just how much of the
We need to keep the questions clear here. The polar melting (andControversy? There's also controversy about evolution, and
there
has
been some controversy on that lately as well), [1]
controversy
about whether astronauts landed on the moon, and controversy about
whether Elvis is dead. Controversy is not evidence. Please let's
stick to the evidence.
polar
ice has melted.
But if what one gets on this list are flippant and derogatory
responses......................
rwt
_______________________________________________
Forum for Physics Educators
Phys-l@carnot.physics.buffalo.edu
https://carnot.physics.buffalo.edu/mailman/listinfo/phys-l
Forum for Physics Educators
Phys-l@carnot.physics.buffalo.edu
https://carnot.physics.buffalo.edu/mailman/listinfo/phys-l
------------------------------
Message: 7
Date: Sat, 4 Apr 2009 15:52:45 -0700
From: "Shapiro, Mark" <mshapiro@Exchange.FULLERTON.EDU>
Subject: Re: [Phys-l] global temperatures
To: 'Richard Tarara' <rbtarara@sprynet.com>, 'Forum for Physics
Educators' <phys-l@carnot.physics.buffalo.edu>
Message-ID:
<F7DA7E5896B79D4F8F7D01E5062D6988018DE8316D97@SFEXCH4.AD.FULLERTON.EDU>
Content-Type: text/plain; charset="iso-8859-1"
The polar ice cover varies during the year quite a bit. The satellite images allow for comparisons at the same time each year.
The minimum ice cover in the summer months has decreased dramatically in these pictures.
Here's a couple of images that show that.
http://irascibleprofessor.com/comments-04-22-07.htm
Dr. Mark H. Shapiro
Professor of Physics, Emeritus
California State University, Fullerton
Phone: 714 278-3884
FAX: 714 278-5810
email: mshapiro@fullerton.edu
web: http://physics.fullerton.edu/~mshapiro
travel and family pictures:
http://community.webshots.com/user/mhshapiro
CSU-ERFA Website: http://csuerfa.org
-----Original Message-----
From: phys-l-bounces@carnot.physics.buffalo.edu [mailto:phys-l-bounces@carnot.physics.buffalo.edu] On Behalf Of Richard Tarara
Sent: Saturday, April 04, 2009 3:48 PM
To: Forum for Physics Educators
Subject: Re: [Phys-l] global temperatures
No..there was a thread--maybe it was of PhysSoc about how the ice was being
measured--from photos, which don't show thickness. I forget all the details
now, just that there was controversy over how the amount of ice was being
determined. Someone had offered that the ice was 'gone' but that certainly
is not yet the case. Again, the 'controversy' that was being discussed (and
I offered this just as an aside anyway) was over the data
collection--basically how reliable IS the data. My point only being that
even the 'data' in the complex issue is sometimes in question. I see that
John Sohl has just offered a partial solution to the data question, but a
solution still awaiting a launch window. Does this mission require the
Shuttle--if so, it is probably dead. If not, what's the hang up?
Rick
----- Original Message -----
From: "John Mallinckrodt" <ajm@csupomona.edu>
To: "Forum for Physics Educators" <phys-l@carnot.physics.buffalo.edu>
Sent: Saturday, April 04, 2009 5:45 PM
Subject: Re: [Phys-l] global temperatures
Rick,
The only news I've heard recently is that the melting appears to be
occurring much faster than any of the models had predicted, but that
wouldn't seem to constitute a "controversy" in the context of this
discussion. Is that what you are referring to?
John Mallinckrodt
Cal Poly Pomona
On Apr 4, 2009, at 2:21 PM, Rick Tarara wrote:
----- Original Message -----_______________________________________________
From: "John Denker" <jsd@av8n.com>
On 04/04/2009 08:02 AM, Rick Tarara wrote in part:The Controversy is exactly over the evidence--just how much of the
We need to keep the questions clear here. The polar melting (andControversy? There's also controversy about evolution, and
there
has
been some controversy on that lately as well), [1]
controversy
about whether astronauts landed on the moon, and controversy about
whether Elvis is dead. Controversy is not evidence. Please let's
stick to the evidence.
polar
ice has melted.
But if what one gets on this list are flippant and derogatory
responses......................
rwt
_______________________________________________
Forum for Physics Educators
Phys-l@carnot.physics.buffalo.edu
https://carnot.physics.buffalo.edu/mailman/listinfo/phys-l
Forum for Physics Educators
Phys-l@carnot.physics.buffalo.edu
https://carnot.physics.buffalo.edu/mailman/listinfo/phys-l
_______________________________________________
Forum for Physics Educators
Phys-l@carnot.physics.buffalo.edu
https://carnot.physics.buffalo.edu/mailman/listinfo/phys-l