Zmena klímy – možný dopad (nielen) na obyvateľstvo - Prohuman

methods have become indispensable. But as far as climatic changes are concerned,
they still serve as auxiliary techniques. Furthermore, their constant development
and improvement of accuracy and precision, the varying object to measure, evoke
worry that they, to a greater extent, will be affected by the problem of homogeneity.
It also must be realized that even though the atmospheric processes are relatively
well-understood and the existing measurement and research techniques,
including supercomputers and modelling procedures, are highly developed,
weather forecasting for time period longer than a couple of days is still problematic.
Predicting climate changes in the nearest 10 or 100 years, not to mention
greater time span, is then incomparably more complicated. What we have now
are only doubtful scenarios, with still little-understood basics and all kinds of
feedbacks. What if we make just a tiny mistake in our studies? Then the outcome
will be completely altered. Therefore every authoritative and firm statements of
individual researchers must be questioned, especially if they are uncritically expressed
by politicians and decision-makers.
Climate change scenario – projection or fiction?
Modern approach to the climate change forecasting relies on General Circulation
Models (GCMs) which simulate the climate system. They are based on basic
physical laws and use hydrodynamic and thermodynamic equations. The numerical
global circulation models are complex and expensive; as a result, only a few
research centres around the world are able develop them. The horizontal spatial
resolution of the contemporary models reaches 100 km, which is a huge step forward
if compared to first attempts in modelling that were made twenty years ago.
Equally important is the growing number of applied variables.
In addition to numerical models, the climate change scenarios employ also
predictions of greenhouse gasses emission as well as other pollutants connected
with both socio-economic development of the world and the ecology actions. In
the Special Report on Emission Scenarios (SRES 2001) an exceptional interest is
given to sustainable development, which allows to design scenarios in which the
greenhouse gasses emission will have become stable by 2050 (scenario B1 and B2).
Depending on what model and which scenario is taken into account, the future
climatic changes may be calculated, but they generally do not reach beyond the
year 2100. The outcome of such projections are often referred to and discussed
in the literature of climatology. For example, it is worth familiarizing oneself with
the Fourth (IPCC 2007) and, currently in development, Fifth Assessment Report of
the IPCC. The raise of average global temperature presented in them is relatively
pessimistic: even if the assumed temperature raise for the 2020–2029 decade will
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