“Is the term ‚climate’ too unspecific for a fruitful discussion?”
A detailed analysis, 10 pages, in: hmtl, in; PDF
Presented at

22nd International  Conference, Pacific Congress on Marine Science and Technology, June 1 - 5 June, 2010,
University of  Hawai`i at  Hilo /USA  

National Conference on  “Climate Change and Future Security“, Loyola Institute of Frontier Energy, 
January 08 - 09, 2011, Loyola College Chennai/India

February 2015

Offshore Wind-parks and mild Winters.
Contribution from Ships, Fishery, Windparks etc.
Online - HERE


see: NATURE 1992, “Climate Change”, Vol. 360, p. 292; http://www.whatisclimate.

Explained by historical examples in 8 PPT/PDF  lectures at:

 Overview below >GO<


Reference links :




How Spitsbergen Heats the World
NEW 2009

Roger PielkeSr. and Climate Definition

- A field of jargon words and misuse
of definitions

-- Rubbish terms: Climate and Climate system --

December 2012
ADDENDUM: Roger Pielke Sr. concerning
“AGU Statement on Climate Change”
August 2013 
by Dr. Arnd Bernaerts

It is a pity. Prof. Roger Pielke Sr ended to run his invaluable weblog “Climate Science: Roger Pielke Sr.“ on November 13, 2012, which he had started with a post on the topic  “What is Climate? Why Does it Matter How We Define Climate?” on July 11, 2005. We discussed his consideration critical in 2007 (here B-211; and B-330). He, as well as his son Roger Pielke Jr. (here E-510), belong to the very few scientists that have addressed the climate definition issue critical. In the last seven years R.  Pielke Sr. did it frequently. In a 1 post on June 15, 2012 (HERE) he commended once again: “The terminology in the field of climate and environmental science is filled with jargon words and the misuse of definitions.” Particularly he opposes the term “climate change”, because the term is being extensively used to mean “anthropogenic caused changes in climate” from nearly ”static“ climatic conditions. Instead only the term “climate” or “climate system” should be used, concluding that the post shall “alert others to the frequent mischaracterization of the climate system”. Regrettably his considerations lack even basic clarity and do not end the mischief in the disastrous climate terminology.  Nothing is solved if “climate change” is replaced by “climate system”. It would require saying precisely and in a meaningful way what “climate” is.

Back in 2005 Roger Pielke Sr. assumed in his first post (see above) that “the climate is the system consisting of the atmosphere, hydrosphere, lithosphere, and biosphere”. Later he merely presented it more detailed definition without altering the basics.  

For example, in “Physics Today” (Nov.2008, p.54f) he wrote:
“For many, the term “climate” refers to long-term weather statistics. However, more broadly and more accurately, the definition of climate is a system consisting of the atmosphere, hydrosphere, lithosphere, and biosphere. Physical, chemical, and biological processes are involved in interactions among the components and the climate system. Vegetation, soil moisture, and glaciers, for example, are ass much a part of the climate system as are temperature and precipitation.” 

The definition is meaningless. It explains nothing. Beside from not mentioning the fundamental relevance of sun ray, “weather” can either be defined as: a system consisting of the atmosphere, hydrosphere, lithosphere, and biosphere. In the same way “nature” can be defined. If weather, climate, nature, need or can only be defined in the same way, than it is misleading to use different words, but claim that there is a distinction. Nevertheless one can often read: “weather is not the same as climate”. That is talking rubbish.

The starting point is that “climate” is generally defined as average weather (by WMO and others) without defining “weather” in the first place (discussed HERE and HERE). It is a comparison between apples and pears. One item has a physical background; the other item is a ‘man-made’ technical mean, which we know as “statistic”. “Weather” consists of many dozen components (AMS-Glossary), which can be described in many hundred ways (see HERE). The statistic of single physical element, or specification of atmospheric behaviour, remain an abstract mean.

On first view Roger Pielke Sr. seems to be aware of it when he writes (June 15, 2012, HERE):  
When change is discussed, the specific component that is being discussed should be presented, such as an increase in annual averaged surface air temperatures, a decrease in the length of growing season etc. Unfortunately, he spoils this approach by the subsequent sentence:

Phrases such as “changes in regional and global climate statistic” could be used. This assumption is wrong. Regardless what kind of regional or global weather statistics is at stake, it is necessary to name the “specific component” individually and precisely.  Assuming that one or several statistical components are able to make-up a weather or a nature “system consisting of the atmosphere, hydrosphere, lithosphere, and biosphere” would always result in a failure. “Climate” is a meaningless term, and scientifically incomprehensive in what ever combination with other words.   

The failure of science to come up with appropriate climate definitions misleads the general public and politicians on how the prevent man-made changes in the atmosphere (more HERE and HERE). The oceans drive the weather and are the main source of changing statistic values. Roger Pielke Sr. addressed this aspect only partly (July 11, 2005; HERE):
                  “Ocean heat content changes are the much more appropriate metric than a globally-averaged surface temperature when evaluating “global warming” in any case.”

Ocean input is much more relevant than this statement suggests, but is too complex to be outlined here any further. Nevertheless, we appreciate his statement highly, as he is one of the very few scientists who have given the ocean more weight. In his closing post Roger Pielke Sr. expressed his intention to “… spend more of my time on research papers.” We wish him well and all success. 

Everything comes from water!!
Everything is maintained through water!
Ocean, give us your eternal power.
Drama: Faust II; Act 2, J. W. v. Goethe (1749-1832)

Addendum: The climate definition by Roger Pielke Sr. in
his essay concerning the
“AGU Statement on Climate Change”,
as published by Judith Curry on August 5, 2013.
HERE: http://judithcurry.com/2013/08/05/agu-statement-on-climate-change/
Posted: 07. August, 2013  
Roger Pielke Sr is a dissenting voice on the panel that wrote the statement. His response to the “AGU Statement on Climate Change” (Adopted December 2003; Revised and Reaffirmed 2007, 2012, August 2013) was posted by Judith Curry on 5th August 2013 at: http://judithcurry.com/2013/08/05/agu-statement-on-climate-change/. In his view the Statement accepted by the Committee incompletely does and/or does not address at all a number of issues. As first point of six he addresses is the question
1. What is the definition of climate and climate change?”,
which he subsequently describes as:  
         Climate is defined here as the statistical description of all 
the elements in the climate system (including the atmosphere, ocean, 
land surface and cryosphere), including both the mean state and any variations over time.    

Climate change is defined as a shift in the statistical description of climate."

A statistic is a statistic of the ‘element’ in question. To say climate is the “statistical description of all elements in the climate system” is circularity, obscure and explains nothing. The common explanation “climate is average (statistical) weather” is scientifically meaningless, if “weather” is not defined in the first place. Circumventing the problem “weather” by replacing it with indefinite “elements” (which can be several thousands) solves nothing. The collection, organization, analysis, interpretation and presentation of data (http://en.wikipedia.org/wiki/Statistics ) from the atmosphere, ocean, land surface and cryosphere does neither represents: weather or climate.

Partly posted at: http://judithcurry.com/2013/08/05/agu-statement-on-climate-change/#comment-361136  

Back to post: Roger Pielke Sr. and Climate Definition  - GO 

Back to Top

Collection of Information, Material, Discussion 
from 2007 to 2012

A Basics & The term Climate B Climate & Climate change C Weather & Climate

114a_ American Meteorology Society’s Glossary concerning the meaning of: weather, climate, and climate change

111_ UNFCCC's "Glossary of climate change acronyms" - Two UNFCCC glossaries with surprises -

113_ Various Glossaries Concerning meaning of:  Climate, climate change, and weather

202 Open Letter on &bdquo;Climate Change:
Reply concerning the letter, 21st October, to the U.S.A. Senate by the listed institutions

206 IPCC says that there are important differences between weather and climate. Is the claim serious science?

211_ What is Climate, had been asked when: Climate Science: Roger A. Pielke Sr Research Group Weblog started in July 2005

212_ Need to talk about, 2009

304_ Just a word on the words "weather" and "climate". Here science fails

305_ What is Weather? Is 'average weather' climate?

330_ Prof. Roger A. Pielke Sr calls for recognition that an equivalence of global warming and climate change is erroneous

315_ How did Thomas A. Blair describe in 1942: Weather, Climate and Climatology?

D Climatology, Politique & International Institutions E Contribution & Papers on UNFCCC F This & That -in brief-

410_ Recently, April 2007, WMO evaluated its role in 'Global Climate Change Issues'

411_ About Valerio Lucarini’s effort to define climate science in 2002

510_ Roger. A. Pielke Jr. on: Misdefining "climate change", 2005

516b_Daniel Bodansky (II) – 1993 – The Convention in place – A Commentary

516c_Daniel Bodansky (III) – 2004 – On how the FCCC emerged

Various V (and more)

Various VI (and more)

VariousVII (and more)

Biography Dr. Arnd Bernaerts



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Essays from 1992 to 1997 on CLIMATE
by Dr. Arnd Bernaerts

“Legal Means for Understanding the Marine and climatic Change Issue”,
p.24 presented at the 28th Annual Conf. of the Law of the Sea Institute, Honolulu


“Conditions for the protection of the global climate”,
p.53 presented at GKSS Research Center Geesthacht


Black Sea-Model Case
--Paper, p.53

--Conf-Paper, p. 6


Four short texts
1994 Moscow

1994 LOS

1993 LOS

1992 Nature

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