How could it happen that more than a dozen of the most prestigious scientific associations signed and submitted this letter on ‘climate change’ without having ensured that the used terminology is sufficiently defined. Read the rest of the entry
The UNFCCC does not define ‘climate’ at all, while
WMO says: 'climate' is average weather.
This website will provide information and ask, does science know what climate is?

Reference links :
How Spitsbergen Heats the World
NEW 2009


Prof. Roger A. Pielke Sr calls for recognition that an equivalence

of global warming and climate change is erroneous


Prof. Roger A. Pielke Sr seems to be one of the few scientists who raises his voice if an incomprehensible scientific terminology is used that may lead to serious confusion or misunderstanding. In a contribution to SCITIZEN in April 2007[1], he addressed the confusion between the terms ‘global warming’ and ‘climate change’[2], claiming that the terms are often used interchangeably. According Pielke this has resulted in the communication of climate change science to policymakers that are seriously flawed.

Although Whatisclimate (WIC) welcomes any serious attempt that requires or achieves more clarity in atmospheric science terminology, it kindly requests any reader to form his own view on Prof. Pielkes reasoning, while WIC constrain its contribution to questions, hoping that they are useful for further reasoning. A short section follows the Extract/Question section with:

Few examples on term: ‘global warming’, and ‘global warming potential’



The matter is about warmer weather during recent decades, respectively about higher temperatures, which can be expressed in ‘warmer average weather statistics’, respectively more precisely: by statistics indicating higher temperature. From here to using a term ‘global warming’ in a clear and undoubtful manner requires further efforts.



Extract from Prof. Roger A. Pielke Sr’s text

Question by Whatisclimate

The terms climate change and global warming are often used interchangeably.


However, even within professional science organizations, there is confusion on the definitions of these terms.


This has resulted in the communication of climate change science to policymakers that are seriously flawed.


The different definitions of climate have done much to confuse policymakers in the discussion of climate science.

WIC: Which definition of ‘climate’ should be used?

WIC: Is R.A.P. aware of the quite meaningless AMS climate definition (“The slowly varying aspects of the atmosphere–hydrosphere–land surface system.”), and was that the reason for not referring to it?

The American Meteorological Society (AMS) definition of “climate change” [3]

See for details the file: A-114

The AMS defines the climate system

See for details the file: A-114

Here we have an inconsistency with the definition even by a very distinguished professional society! Climate, as defined by the AMS, is focused on the atmosphere, while the climate system consists of the atmosphere, hydrosphere, lithosphere, and biosphere. No wonder policymakers misapply this terminology.

WIC: Actually the claim of R.A.P is not fully correct, as AMS refers concerning climate to: the atmosphere–hydrosphere–land surface system; and concerning ‘climate system’ to: the atmosphere, hydrosphere, lithosphere, and biosphere. Nevertheless, the presentation of terms is inconsistent

Even more misleading is the use of the term "global warming" and "climate change" interchangeably. The AMS Glossary of Meteorology does not even include this term (see)!

WIC: Global weather consists of presumably several hundred elements, ditto-average weather, this includes the element: temperature. If the temperature change on a global basis one can call it ‘global warming’ but not ‘change of average weather’ (or climate change).

Global warming (or global cooling) means that heat content changes have occurred in the Earth’s climate system. The surface average temperature trend has been the traditional metric used to assess this heat content change (e.g. see the text in the 2005 National Research Council report that starts on page 19 ).


(Ca. one page text not reproduced)


The greater importance of heterogeneous aerosol and landscape human climate forcing relative to the more spatially homogeneous radiative forcing of added CO2 in terms of how atmospheric weather features are affected was documented in

Matsui, T., and R.A. Pielke Sr., 2006: Measurement-based estimation of the spatial gradient of aerosol radiative forcing . Geophys. Res. Letts., 33, L11813, doi:10.1029/2006GL025974.

These heterogeneous human climate forcings can occur with or without global warming, and appear to alter the climate system to the greater extent than does the radiative effect of CO2.

WIC asks:

Are anthropogenic induced aerosols and altered landscape, and increased CO2 are not only relevant on atmospheric physical dynamics, which will alter local, regional and global weather pattern? Is a reference to “human climate forcing” a non-explanation, which might even misleading?

WIC asks:

Why does R.A.P. puts forcing means in relation to ‘atmospheric weather features’ (which seems reasonable and correct approach), but thereon switches – without any explanation - these forcing matters to: “ heterogeneous human climate forcings”?

It is time for the assessment and policy communities and the media to recognize that an equivalence of global warming and climate change is erroneous. 

WIC agrees and asks:

How could it happen that a top scientist needed to raise this question in the year 2007, and many of his colleagues do neither listen, nor stopped using the terms interchangeable? Is that stupidity, or intention?

 Few examples on term: ‘global warming’, and ‘global warming potential’


The term "global warming" is a specific example of the broader term climate change, which can also refer to global cooling. In common usage the term refers to recent warming and implies a human influence. [5] The United Nations Framework Convention on Climate Change (UNFCCC) uses the term "climate change" for human-caused change, and "climate variability" for other changes. [6] The term "anthropogenic global warming" is sometimes used when focusing on human-induced changes.

2001; International Petroleum Industry Environmental Conservation Association

Global Warming

The view that the earth’s temperature is being increased, in part due to emissions of greenhouse gases associated with human activities such as burning fossil fuels, biomass burning, cement manufacture, cow and sheep rearing, deforestation and other land-use changes.

2001; International Petroleum Industry Environmental Conservation Association

Global Warming Potential, or GWP

A time dependent index used to compare the radiative forcing, on a mass basis, of an impulse of a specific greenhouse gas relative to that of CO 2 . Gases included in the Kyoto Protocol are weighted in the first commitment period according to their GWP over a 100-year time horizon as published in the 1995 Second Assessment Report of the IPCC. In that report, a kilogram of methane, for example has a radiative force of about 21 times greater than that of a kilogram of CO 2 .The GWP of CO 2 is defined as 1, thus methane has a GWP of 21 over the 100-year time horizon.

Intergovernmental Panel on Climate Change (Global Warming, NONE)  

Global Warming Potential (GWP)

An index, describing the radiative characteristics of well-mixed greenhouse gases , that represents the combined effect of the differing times these gases remain in the atmosphere and their relative effectiveness in absorbing outgoing infrared radiation. This index approximates the time-integrated warming effect of a unit mass of a given greenhouse gas in today’s atmosphere, relative to that of carbon dioxide.



[2] Ditto; Scitizen , 24 Apr, 2007 01:16 pm, [OPINION] Confusion in the Definitions of Global Warming and Climate Change



Essay 2010
Is the term ‚climate’ too unspecific?
Pages 10

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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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