What is the climate system able to do ‘on its own’?

The climate of the Earth, like planetary climates in general, is broadly controlled by solar irradiation, planetary albedo and emissivity as well as its rotation rate and distribution of land (with its orography) and oceans. However, the majority of climate fluctuations that affect mankind are internal modes of the general circulation of the atmosphere and the oceans. Some of these modes, such as El Nino-Southern Oscillation (ENSO), are quasi-regular and have some longer-term predictive skill; others like the Arctic and Antarctic Oscillation are chaotic and generally unpredictable beyond a few weeks. Studies using general circulation models indicate that internal processes dominate the regional climate and that some like ENSO events have even distinct global signatures. This is one of the reasons why it is so difficult to separate internal climate processes from external ones caused, for example, by changes in greenhouse gases and solar irradiation. However, the accumulation of the warmest seasons during the latest two decades is lending strong support to the forcing of the greenhouse gases. As models are getting more comprehensive, they show a gradually broader range of internal processes including those on longer time scales, challenging the interpretation of the causes of past and present climate events further

Problemy akustyczne elementów i układów mikrohydraulicznych

This paper presents selected applications of the miniaturized hydraulic components offered by specialized manufacturers and some results of the authors' own research on microflows, including results of hydraulic microfeeder vibration measurements performed by the touchless method using a laser vibrometer. The latter was chosen in order to eliminate measuring instrument influence on the investigated microhydraulic object. Special attention was focused on acoustic problems: noise sources and methods of noise reduction.W pracy przedstawiono wybrane przykłady zastosowań zminiaturyzowanych elementów hydraulicznych proponowanych przez wyspecjalizowanych producentów oraz podano wyniki niektórych prac własnych nad zjawiskami związanymi z mikroprzepływami. W artykule prezentuje się m.in. wyniki pomiarów drgań zaworu przelewowego mikrozasilacza hydraulicznego wykonane za pomocą wibrometru laserowego - metodą bezdotykową. Wykorzystanie do pomiarów w obszarze mikrohydrauliki wibrometru laserowego podyktowane było koniecznością wyeliminowania wpływu przyrządów pomiarowych na badany obiekt. Szczególną uwagę skupiono na problemach akustycznych: źródłach hałasu i metodach jego redukcji