Silly? Very Silly?? Naive???
Posted by Dr. Arnd Bernaerts, April 2014

Climate in a narrow sense is usually defined as the average weather,
or more rigorously, as the statistical description in terms of the mean and variability of relevant quantities over a period of time ranging from months to thousands or millions of years. The classical period for averaging these variables is 30 years, as defined by the World Meteorological Organization. The relevant quantities are most often surface variables such as temperature, precipitation and wind. Climate in a wider sense is the state, including a statistical description, of the climate system.

Climate  [1]

[1] The term ‘climate’ (used in Ancient Greek klima, meaning inclination of the sun) was used to describe the average weather at a location according the season. It was a layman’s term over 3000 years. As a scientific term it came in use only during the last decades. [A], [B], [C]; more HERE

in a narrow sense [2]

[2] What is CLIMATE in a wider sense?

is usually defined [3]

[3] Is there any “unusual” CLIMATE definition? What shall “usual” explain? 

as the average[5]
weather [4],[6].

[4] The term ‘weather’ is not listed in the IPCC-Glossary! The core term is not defined! Silly? A joke?

[5] ‘Weather’ presumably consists of up to several hundred parameters or descriptions. More details HERE, and HERE..

[6] ‘Weather’ is also a layman’s term since immemorial times, as described in the AMS-Glossary: “As the state of the atmosphere, mainly with respect to its effects upon life and human activities.” While it is a perfectly common term in the layman’s sphere, it is totally insufficient for scientific work.

or more rigorously [7] ,

[7] If the initial explanation ‘explains’ nothing (1-5), a more ‘rigorous’ approach explains either nothing.

as the statistical description [8]

[8] The word statistic is a quantity computed from sample data. A statistical description is a synonym of statistic. Once a statistic always a statistic.

in terms of the mean [9]

[9] Which ‘terms’, which ‘means’?

and variability [10]

[10] Which variability is meant? IPCC-Glossary cause confusion if saying: “Climate variability refers to variations in the mean state and other statistics (such as standard deviations, the occurrence of extremes, etc.) of the climate on all spatial and temporal scales beyond that of individual weather events. Variability may be due to natural internal processes with the climate system (individual variability, or anthropogenic external forcing (external variability).” Do they mean ‘weather variability’ or statistical variability’?

of relevant quantities [12]

[12] Who defines what is a ‘relevant quantity’?

over a period of time ranging from months to thousands or millions of years [13]. 
 

[13] What a flaw! How can science work with such nonsense? How can the general public and politics understand and evaluate ‘scientific findings’?

The classical period for averaging these variables is 30 years, as defined by the World Meteorological Organization. [14]

[14] Wrong, at least misleading! Only once the predecessor of the WMO agreed in 1935 that the period from 1901 to 1930 should be used to express departures from mean data^x). Not only has this fixed indicator been abandoned, but also the time span of 30 years. What is now a ‘change’?
           ^x) Kincer, J.B., 1935; Monthly Weather Review, 63, 342-344, available online at:   
                   http://docs.lib.noaa.gov/rescue/mwr/063/mwr-063-12-0342.pdf.

The relevant quantities [15] are most often surface [16] variables

such as temperature, precipitation and wind [17]

[15] see [above 12]

[16] What shall the word ‘surface’ indicate?

[17] ‘Weather’ consists of several hundred parameters, see [5]

Climate in a wider sense [18] is the state, including a statistical description, of the climate system [19] ; [IPCC definition, next box below]

[18] The whole sentence is confusing and utterly nonsense. It actually says: “Climate is the state of the climate system”. According IPCC definition, climate is statistic. Why do the authors include in the sentence: “including a statistical description”.

[19] Deliberate or naive? The definition of ‘climate system’ explains nothing. The same definition could be used to explain ‘nature’, consisting “of the atmosphere, the hydrosphere, the cryosphere, the lithosphere and the biosphere, and the interactions between them.”

IPCC-Glossary says: The climate system is the highly complex system consisting of five major components: the atmosphere, the hydrosphere, the cryosphere, the lithosphere and the biosphere, and the interactions between them. The climate system evolves in time under the influence of its own internal dynamics and because of external forcings such as volcanic eruptions, solar variations and anthropogenic forcings such as the changing composition of the atmosphere and land use change.