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changes? Or maybe they have already become the indicator of climatic catastrophe?
What is climatic catastrophe and how does it manifest itself?
This concept, expressed alike in numerous languages, means simply the cataclysm
in existing climate. What is catastrophe, then? The word is of Greek origin
(katastrophē – “overthrow”) and, according to Merriam-Webster Dictionary
it means “a violent and sudden change in a feature of the earth” The definition
emphasizes the suddenness as a major feature of catastrophe so the question
may be raised whether the expected climate changes will happen rapidly. In attempting
to answer this, it is proper to investigate the history of climate from
the last 100–200 years, as the knowledge of the changes that happened during
those times is quite broad, since instrumental observations have been available
(Burroughs 2009). Figure 1 shows variability of average temperature of the air in
winter (December–February) on the weather station at Krakow – Observatory. It
has the longest continuous record of temperature in Poland, which is an excellent
representation of the climatic conditions for the southern part of the country. The
data demonstrates a great variability of the values and an increasing long-term
trend. Similar graph shows global annual average temperature in 1861–2010 (fig.
2). Although it shows the average deviation from mean temperature of 1961–1990
period, it clearly proves that the global annual mean temperature increased about
0.7°C. From climatologic point of view, it is rather alarming growth and if this
trend continued for the next 100–300 years, the climatic changes, including global
warming, would be catastrophic (rapid retreat of glaciers, sea level rise, changes
in climate and vegetation zones, etc.).
Climate changes, and especially air temperature vacillation can be examined
thanks to proxy data, although this may result in poorer exactness. Many researchers,
including geologists, glaciologists, botanists, historians, and archaeologists,
provide priceless climatic data, which allows to reconstruct the past in
historical or geologic time scale. The outcomes are generally known and unambiguous:
they confirm considerable climate vacillations in the past ages, and also
indicate that the difference between the highest and lowest annual mean temperature
values can reach even 10°C. It must be remembered though that these
changes were gradual. It has been estimated that even during the most sudden
cases of warming, the increase of annual average temperature was never greater
than only tenths degree Celsius per century.
All the data confirm unequivocally that climatic changes and variability were
present in the Earth’s history and are currently in progress. The reconstructions
oblige us to seek for the causes of the changes, but they also make it possible
to model climate. In connection with what has already been discussed, and in
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