Air temperature ; Climate ; Cloud ; Cloud cover ; Cracow ; Poland ; Solar radiation ; Thermal regime ; Topoclimate
Apart from total cloudness, cloud genera considerably influence radiation conditions in local scale as well as the daily air temperature course. The paper presents air temperature course during the occurence of particular cloud genera and during
the cloudness days, on the example of climatological data from Cracow. The analysis shows that the least impact on thermal conditions both in summer and winter, have high clouds. Their presence does not limit the input of solar radiation and on days with Ci, Cc
and Cs clouds the air temperature course is close to that of the cloudness day. Therefore the weather with high clouds, regardless total cloudness, may be treated as the radiative one, favourable for the differenciation of topoclimatic conditions. - (BJ)
The history of the cloud-seeding operations and experiments is described first, followed by discussion of 3 spatial statistical techniques that assist in the assessment of the contribution of cloud-seeding operations. Lastly, an attempt is made
to utilize hydrological parameters for the purpose of evaluating the effects of cloud seeding.
Incoming longwave radiation enhancement by cloud cover
Atmosphere ; Atmospheric moisture ; Cloud ; Cold area ; Concept ; Model ; Mountain ; Radiation
The effect of cloud cover on incoming longwave radiation reaching the ground surface is investigated using an analytic procedure. Results show that the contribution of a cloud deck depends not only on cloud type, but also on cloudless emissivity
Long-term observations of cloud cover in Cracow (1792-1999)
Climate ; Climatic variability ; Cloud ; Cloud cover ; Cracow ; Data base ; Nineteenth Century ; Poland ; Twentieth Century
Cracow's series of nephological observations is unique in Europe. Neither the place of observations nor the methods of estimation of the degree of cloud cover nor the definition of cloud genera have changed significantly for about one hundred years
Arizona ; Climatic variation ; Climatic warming ; Cloud ; Global change ; Mexico ; Monsoon ; Subtropical zone ; United States of America
Author and students investigate whether subtropical, convective clouds warm the atmosphere by trapping earth's heat or they cool it by reflecting sunshine. Study is conducted during the summer monsoon of Arizona and northwest Mexico. They found via
infrared sensors that the higher clouds had a mainly warming effect. The lower clouds cooled the temperatures when they covered more than 70% of the sky and yielded precipitation. The warming effect was quite evident at night and in the mountains
Discussion of the preliminary results from ERBE (Earth radiation budget experiment), available for April 1985, highlighting the role of clouds in the climatic system and climatic change (greenhouse effect).
The semi-empirical water cloud model can be implemented to derive spatial values of biophysical parameters from remotely sensed radar data for use throughout different disciplines of physical geography. The water cloud model formulation
Experimental investigation of the velocity of a sand cloud blowing over a sandy surface
distribution of particles in a blowing sand cloud and variation of the mean velocity of the blowing sand cloud with height. An attempt is made to discuss the particle turbulence, the velocity fluctuation of particles passing a fixed point, in a blowing sand
The impact of clouds on climate can be determined by numerical models or satellite observation. The article presents the results of the ERBE measurement campaign, which concluded that the presence of clouds decreases the intensity of longwave
in the case of four different cloud types. The results show that the net fluxes on the surface depend only on the height of the clouds. It was also found that the net flux at the top of the cloud decreases sharply close to zero; as the cloud absorbs most
Dry heat exchange and skin temperature in subjects outdoors at fluctuated cloud cover
Bioclimatology ; Cloud ; Cloud cover ; Heat exchange ; Human bioclimatology ; Poland ; Summer ; Temperature
as thermal sensations in subjects during varying cloud cover. Preliminary results show clear relationships between DHE as well as Tsk and intensity of solar radiation (Kglob). In fluctuated cloud cover significant changes of DHE, Tsk and thermal sensations
The spatio-temporal variation of total cloud amount is analyzed for 75 stations on Qinghai-Tibet Plateau during 1971-2004. Correlation analysis demonstrates that the total cloud amount is negative with sunshine duration and diurnal temperature range
, and is positive with precipitation and the relative humidity, respectively. The negative correlation is consistent with the radiative effect of cloud. Discussion implies that the decrease of total cloud amount is possibly due tothe variation of atmospheric aerosol
Climatology ; Cloud ; Dynamical climatology ; Earth's globe ; Evaporation ; Global change ; Water cycle;Water circulation
Surface-based observations of total cloud amount have been collected from historical records for four continents : North America, Europe, India and Australia. The records extend from 1900 to around 1985. 86 % of the 350 individual station records
show an increase in total cloud amount, espacially in North America and Australia.
Mountain cloud forest conservation and research: a synopsis
Cogent article on an inclusive definition for mountain clouds forests, their importance in hydrology and biodiversity and a discussion of eight kinds of threats to their survival. Discussion of actions and research needs required to meet those