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



About Valerio Lucarini’s effort to define climate science in 2002[1]

D - 411

NOTE: Question, Info, Comment etc are from ‘whatisclimate’,

Ditto if marked: WIC or otherwise; Sept.07, 2007

Valerio Lucarini’s paper: “Towards a definition of climate science”, does not spend much time on explaining how climate science explains ‘climate science’, but talks about other matters. Actually Lucarini never even attempts to define ‘climate science’, but practically speaks only about “Uncertainties in climate science”[1] , and is concerned with computer modeling. Subsequently his Conclusion of ca. 350 words mentions the term ‘climate science’ not once. Lucarini’s paper is a demonstration how the term ‘climate’ can be easily ‘twisted’ and misused.

In his chapter on “ Uncertainties in climate science”, he starts saying firstly: “Due to the complexity of the system, climate dynamics is chaotic and is characterized by a large natural variability on different temporal scales”, and thereon continues to emphasize that “the actual situation is much more problematic because even for the atmosphere, the database go back in time no more than 4–5 decades”[3]. This shows that a simple fact is ignored, namely that only the atmosphere is part of a system and climate a mere ‘imagination’, respectively arbitrarily selected and compiled statistics. This shall be further analysed by putting some questions or remarks to the Lucarini’s Introduction.

Lucarini’s paper: “Towards a definition of climate science”

Here: Introduction

Question, Info, Comment etc are from ‘whatisclimate’,


The climate is defined as the mean physical state of the climatic system,

WIC-Comment: It is a definition out of the blue; and makes no sense.

which is constituted by atmosphere, hydrosphere, cryosphere, lithosphere and biosphere, which are intimately interconnected.

WIC-Comment: climatic system is as general and vague as saying: ‘natural system’, and explains, as the UNFCCC on ‘climate system’[4] nothing.

Therefore, the climate is determined by a set of time-averages of quantities that describe the structure and the behaviour of the various parts of the climatic system, as well as by the correlations among them.

WIC-Comment: If Lucarini speaks of ‘a time-averages of quantities’ he actually has in mind: weather-statistics. The sentence sounds less pompous if climate is replaced by ‘ weather averages’, see: Footnote[5].

In the very definition of climate there is an ambiguity and an element of subjectivity because the extension of the time interval over which the statistics are made is not determined a priori, but is operationally chosen depending on the goal of the research.

WIC-Comment: The claimed ambiguity of climate is due to the fact that it is a mere statistical tool, which neither sets precise conditions which data comprise weather, and over which time periods[6]

The presence of such a weak foundation strongly determines all the features of climate science.

WIC-Comment: The weak foundation is the scientific weakness of meteorology, respectively of atmospheric science.

This weakness does not imply that this is a bad science, as stated by various politicians and opinion makers around the world, but it is a natural consequence of the fact that the system, subject to the studies of the climate scientists, is extremely complex.

WIC-Comment: ‘climate science’ cannot be more than a ‘science on average weather’. If meteorology does not understand, and measure all and every relevant aspect of atmospheric behaviour, climate science can practically not exist.

This complexity of the climatic system is such that the feedback between the various parts play an essential role. It makes little sense to define single elements and processes, when it is more sensible to consider it as a non separable ‘body’, a ‘living organism’ which cannot be solved, i.e. explained in simple terms, as the origin of the word ‘complex’ explains.

WIC-Comment: The atmospheric system, together with meteorology is complex, but instead to acknowledge this fact, they speak about ‘climate system’ that explains nothing, respectively not more as: the average weather system over “a period of time ranging from months to thousands or millions of years”, see Footnote 5.

Therefore, it is conceptually incorrect to expect that climate science could provide answers having comparable precision and similar structure to those provided by sciences that investigate less complex systems.

WIC-Comment: Lucarini is silent about which type of science is concerned with less complex systems., not realizing that climate is only the statistical off-shot of meteorology.

The complete understanding of the climate system is an open problem that may never be solved: this makes the study of the climate a scientific enterprise of exceptional interest.

WIC-Comment: The climate system will never be solved; as such system does not exist.

The urgency and the pressure for providing the policymakers with information that is necessary for the implementation of long-sighted policies gives climate science an extremely relevant sociopolitical role which, in turn, contributes to shaping the structure, goals and priorities of climate science.

WIC-Comment: ‘Climate science’ would do a great service to the politics and the general public to acknowledge that climate is a layman’s term and is of little help in the scientific field.

The latest report (Houghton et al., 2001) of the International Panel on Climate Change (IPCC; see, has recently been criticized for lacking quantitative estimations of the uncertainties of the projections of climate change (Reilly et al., 2001).

WIC-Comment: As long as IPCC puts much too little attention to the climatic relevance of the oceans, any projection in ‘average weather changing pattern over a longer period of time’ will remain gross speculation.

An assessment of such uncertainties is needed in order to provide the governments with clear baselines to be able to initiate a process of rational decision making.

WIC-Question: Would it not be better and more prudent to define the meaning of climate reasonably, clearly avoiding the conventional definition about the average weather over a longer period of time.

WIC-Conclusion: Valerio Lucarini’s claim to contribute to the understanding of the meaning of “climate science” is little more than a farce. Instead of discussing the matter in academic terms, he is mainly concerned with the usage of average data for computer modelling, and for this purpose he presents his view on understanding the climatic matter. His conclusion start with the sentence: “The previously presented studies do not absolutely have the last word in terms of climate change projections; their main merit is that they present an epistemologically correct instrument of investigation.” That says not very much about a definition on climate science.


[1] Valerio Lucarini, “Towards a definition of climate science”, in: International Journal Environment and Pollution, Vol. 18, No. 5, 2002, p. 413 -422.

[2] Title of section 2.

[3] The full text goes as follows: Due to the complexity of the system, climate dynamics is chaotic and is characterized by a large natural variability on different temporal scales that would cause non-trivial difficulties in detecting trends in statistically relevant terms, even if the observational data were absolutely precise. The actual situation is much more problematic because even for the atmosphere, which is the observationally best-known component of the climatic system, the database of observations having global extension, good reliance and good temporal frequency go back in time no more than 4–5 decades.

[4] UNFCCC, Article 1, subpara.3: "Climate system" means the totality of the atmosphere, hydrosphere, biosphere and geosphere and their interactions.

[5] Therefore, the average weather is determined by a set of time-averages of quantities that describe the structure and the behaviour of the various parts of the weather system, as well as by the correlations among them.

[6] According the Intergovernmental Panel on Climate Change (IPCC) Glossary, everyone is free to choose “a period of time ranging from months to thousands or millions of years”,


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

Chronicle Archive
Talk About Topics
Click for archive 2012
Click for archive 2011
Click for archive 2010
Click for archive 2009
Click for archive 2008
Click for archive 2007

Want to comment?
Email us!

Previous archives Year 2010
Year 2009

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

Note to User
Kindly indicate:
as source
Terms & Conditions