Climate change impact
Inadvertent climate change The climate naturally changes. An alternation of the warmer and colder periods in the past can be deduced e.g. from the polar ice or from the deep-ocean sediments. The last glacial period finished approximately 12 000 years ago, currently we are situated in the warmer period. The main reason for altering the glacial and inter-glacial periods is cyclical variation in the Earth´s movements around the Sun. The Earth rotates around the Sun in an elliptical curve whose parameters periodically change, which results in the changes of the distribution of solar radiation over the Earth´s surface. This hypothesis was deduced by Serbian scientist Milutin Milankovic in the first half of the 20th century. The paleo-climatological data confirmed a tight relation between the changes of global temperature and the changes of the elliptical curve of the Earth. The natural changes occur slowly, the durations of glacial and inter-glacial periods are of the order of tens of thousands of years. Therefore, the mankind would probably simply adapt for such slow changes. Nevertheless, there is a concern that some human activities may cause a much faster climate change. The main such activity is the use of fossil fuels. Greenhouse effect
The most important greenhouse gasses are carbon dioxide (CO2), methane and water vapour, which can be found naturally in the atmosphere. The air temperature near the surface would be below the freezing point without them, thus the greenhouse gasses are essential for the life on the Earth. Since the beginning of industrial revolution in the 18th century people intensively use the energy concentrated within the millions of years in fossil fuels. The burning of fossil fuels produces huge amount of carbon dioxide; the concentration of CO2 in the atmosphere incessantly grows. This can intensify the natural greenhouse effect and cause a warming of the atmosphere much faster than the natural changes. Feedbacks in climate system The climate system is very complicated; there are many feedbacks between its individual components. The increase of air temperature stimulates many processes which can accelerate (positive feedbacks) or attenuate (negative feedbacks) additional warming. The most important feedbacks are
Except these main feedbacks there are many other relations in the climate system, which can accelerate or attenuate warming in changing climate conditions. ![]() Climate models The only possible way to investigate an extent and a possible impact of climate change is the detailed modelling of climate system. The model must work according to the physical laws determining the atmospheric and ocean circulation and the above mentioned feedbacks must be built in. The climate model is a computer programme simulating the evolution of the climate system from an initial state. The structure of the model approximately corresponds to the structure of the real climate system. The model is composed of interacting components (atmosphere model, ocean model, sea ice model and surface model) and supplemented by a chemical model, which simulates the effect of compounds affecting the energy balance of the climate system (primarily CO2). The first attempts to use the computers for climate system modelling were done many decades ago; nevertheless, the fully coupled atmospheric-ocean models are used since ´90s. Currently, the climate models represent a fundamental data source for investigation of the climate system and the climate change impact. |
Research Activities |
The research in the Institute of Hydrodynamics is focused primarily on the applicability of the climate model outputs. Current climate models well simulate the evolution of huge atmospheric structures; nevertheless, they cannot provide detailed information about the meteorological variables near the Earth´s surface. This problem is in particular related to the precipitation, which is a fundamental input to any climate change impact study. For this reason, the research is focused primarily on developing methods, which allow deriving the detailed information about the effect of climate change on a hydrological cycle.
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