Comparison of marine insolation estimating methods in the adriatic sea

Abstract

− We compare insolation results calculated from two well-known empirical formulas (Seckel and Beaudry's SB73 formula and the original Smithsonian (SMS) formula) and a radiative transfer model using input data predicted from meteorological weather-forecast models, and review the accuracy of each method. Comparison of annual mean daily irradiance values for clear-sky conditions between the two formulas shows that, relative to the SMS, the SB73 underestimates spring values by 9 W m -2 in the northern Adriatic Sea, although overall there is a good agreement between the annual results calculated with the two formulas. We also elucidate the effect on SMS of changing the 'Sun-Earth distance factor ( f )', a parameter which is commonly assumed to be constant in the oceanographic context. Results show that the mean daily solar radiation for clear-sky conditions in the northern Adriatic Sea can be reduced as much as 12 W m -2 during summer due to a decrease in the f value. Lastly, surface irradiance values calculated from a simple radiative transfer model (GM02) for clear-sky conditions are compared to those from SB73 and SMS. Comparison with in situ data in the northern Adriatic Sea shows that the GM02 estimate gives more realistic surface irradiance values than SMS, particularly during summer. Additionally, irradiance values calculated by GM02 using the buoy meteorological fields and ECMWF (The European Centre for Medium Range Weather Forecasts) meteorological data show the suitability of the ECMWF data usage. Through tests of GM02 sensitivity to key regional meteorological factors, we explore the main factors contributing significantly to a reduction in summertime solar irradiance in the Adriatic Sea.

Population dynamics of Eudendrium racemosum (Cnidaria, Hydrozoa) from the North Adriatic Sea

“…Colonies always disappeared in the coldest part of the year but the duration of the absence period may vary from one year to another. In particular, colonies were not found for 2 months in 2006-2007 (February andMarch) and up to 4 months during 2007-2008-2011. Variations in the beginning and duration of the fertility period were also observed: for example in 2008, E. racemosum produced gonophores in two different moments, from May to July and in October, while in 2009 and 2011 the gonophore production began in May and lasted until September.…”

“…Data were collected by the water temperature transducer T020 TTA placed on the sea surface in the Ancona's NT station. Irradiance data were obtained from Byun and Pinardi 2007. In order to check the presence of hydrorhizae probably acting as resting stages, small pieces of substrate were detached from the rocky wall in the sampling area during winter and spring, and then, the pieces were observed under stereomicroscopy.…”

Mediterranean Forecasting System: forecast and analysis assessment through skill scores

“…The bias is between 0 and 0.1 • C and it is generally negative in the subsurface while it is positive at the surface during the summer months. The reason for that was studied in the past by Byun and Pinardi (2007). This is due to the overestimation of the solar incoming radiation with in our model (an approximate form of the Smithsonian formula modified by Reed, 1977).…”

Temporal variations in growth and reproduction of Tedania anhelans and Chondrosia reniformis in the North Adriatic Sea

“…Data of solar irradiance in the area have been reported by Byun & Pinardi (2007). For estimating of the food availability in the Conero area, we used the chlorophyll concentrations obtained during an ARPAM coastal monitoring campaign from January to November 2009 in the station WGS84 (43°34 0 53.6 00 N-13°34 0 17 00 E) with the Idronaut Ocean Seven plus Probe (Cicero & Di Girolamo, 2001).…”