Variability of Atmospheric Cloudiness and Sunshine Duration in the Câmpulung Muscel Depression (Argeș – România)

January 8, 2019


Atmospheric cloudiness  and sunshine duration are the most important climatic parameters in assessing the  radiative potential of a certain region which influences ecosystems,  particularly, plants grow and  developement. Cloudiness represents the totality of the clouds of the sky, or, in an exact sense, the degree of  sky coverage with clouds, expressed in tenths of overcast covered sky. The degree of sky coverage and the clouds types are dependent on the evolution of air masses, on the afferent  atmospheric fronts and underlying surface features. The sunshine duration  represents the time interval corresponding to the presence of the solar disk on the sky and it  is expressed in hours and tenths of  hour. The two parameters are in an inverse relationship, the high cloudiness  causes a  low sunshine. In this paper, there was analysed annual, seasonal, monthly cloudiness and sunshine duration variation, in the Câmpulung Depression, in the 1961-2010 period, 1971-2010-period respectively.  In  this region,  the cloudiness regime records a maximum in April and a minimum in August, while the sunshine duration has a  minimum in December and a maximum  in July.


Cloudiness frequency, Lower cloudiness, Total cloudiness, Percentage of possible sunshine, Sunshine duration.


Angell J.K., 1990. Variation in United States cloudiness and sunshine duration between 1950 and the drought year of 1988. Journal of Climate, 3, 296-308.

Brázdil R., Flocas A.A., Sahsamanoglou H.S., 1994. Fluctuation of sunshine duration in Central and South- Eastern Europe. International Journal of Climatology, 14, 1017-1034.

Curto J., Also E., Pallé E., Solé G., 2009. Sunshine and synoptic cloud observations at Ebro Observatory, 1910-2006. International Journal of Climatology, 29, 2183-2190.

Dai A., Karl T.R., Sun B., Trenberth K.E., 2006. Recent trends in cloudiness over the United States: A tale of monitoring inadequacies. Bulletin of the American Meteorological Society, 87, 597-606.

Henderson-Seller A., 1986. Cloud changes in a warmer Europe. Climatic Change, 8, 25-52.

Henderson-Seller A., 1989. North American total cloud amount variations this century. Paleogeo -graphy, Paleoclimatology, Paleoecology, 75, 175-194.

Jones P.A., Henderson-Seller A., 1992. Historical Records of cloudiness and sunshine in Australia. Journal of Climate, 5, 260-267.

Kaiser D.P., 1998. Analysis of total cloud amount over China, 1951-1994. Geophysical Research Letters, 25, 3599-3602.

Li W., Hou M., Xin J., 2011. Low-cloud and sunshine duration in the low-latitude belt of South China for the period 1961-2005. Theoretical and Applied Climatology, 104, 473-478.

Lynch D.K., 1996. Cirrus clouds : Their role in climate and global change. Acta Astronautica, 38, 859-863.

Mace G.G., Benson S., Kato S., 2006. Cloud radiative forcing at the Atmospheric Radiation Measurement Program Climate Research Facility: 2. Vertical redistribution of radiant energy by clouds. Journal of Geophysical Research Letters, 111, D11S91.

Maugeri M., Bagnati Z., Brunetti M., Nanni T., 2001. Trends in Italian total cloud amount, 1951-1996. Geophysical Research Letters, 28, 4551-4554.

Milewska E.J., 2004. Baseline cloudiness trends in Canada 1953-2002. Atmosphere-Ocean, 42, 267-280.

Pallé E., Butler C.J., 2002. Comparison between sunshine records and synoptic cloud observations: a case study for Ireland. Physics and Chemistry of the Earth, 27, 405-414.

Quante M., 2004. The role of clouds in the climate system. Journal de Physique, IV, 121, 61-86.

Sanchez-Lorenzo A., Calbó J., Matin-Vide J., 2008. Spatial and temporal trends in sunshine duration over Western Europe (1938-2004). Journal of Climate, 21, 6089-6098.

Sanchez-Lorenzo A., Calbó J., Wild M., 2012. Increasing of cloud cover in the 20th century: review and new findings in Spain. Climate of the Past, 8, 1199-1212.

Sun B., Groisman P., 2000. Cloudiness variations over the Former Soviet Union. International Journal of Climatology, 20, 1097-1111.

Sun B., Mokhov I.I., 2001. Recent changes in cloud-type frequency and inferred increases in convection over the United States and the Former USSR. Journal of Climate, 14, 1864-1880.

Sun B., 2003. Cloudiness over the contiguous United States: Contemporary changes observed using ground – based and ISCCP D2 data. Geophysical Research Letters, 30, 1053.

Sun B., Groisman P., 2004. Variations in low cloud cover over the United States during the second half of the twentieth century. Journal of Climate, 17, 1883-1888.

Warren S.G., Eastman R.M., 2007. A survey of changes in cloud cover and cloud types over land from surface observations, 1971-`96. Journal of Climate, 20, 717-738.

Xia X., 2010. Spatiotemporal changes in sunshine duration and cloud amount as well as their relationship in China during 1954-2005. Journal of Geophysical Research, 115, D00K06.

Author Details

Chichirez Cristina-Mihaela

  • Department of Marketing and Medical Technology - Carol Davila University of Medicine and Pharmacy Bucharest
  • Google Scholar
  • RAJAR Journal