scholarly journals Comparison between Two Extreme NAO Winters and Consequences on the Thermal Regime of Lake Vendyurskoe, Karelia

2005 ◽  
Vol 6 (5) ◽  
pp. 775-783 ◽  
Author(s):  
Osama Ali Maher ◽  
Cintia Bertacchi Uvo ◽  
Lars Bengtsson
Keyword(s):  
Water Temperature ◽  
Thermal Regime ◽  
Regional Climate ◽  
Salt Content ◽  
Sharp Change ◽  
Average Water Temperature ◽  
The North ◽  
Average Water ◽  
The North Atlantic Oscillation ◽  
Cover Thickness

Abstract For 10 consecutive winters, measurements were carried out in Lake Vendyurskoe, Karelia, Russia. The aim of these measurements was to investigate some of the physical processes in this small shallow lake during its ice-covered period. Detailed measurements of ice thickness and condition, snow thickness, water temperature, salt content, and currents were developed into a database. Within this database are the winters 1994/95 and 1995/96, which are characterized by a very sharp change between positive and negative phases of the North Atlantic Oscillation (NAO). This note investigates and compares the effects of these two NAO phases on the regional climate and their relation to the thermal regime of Lake Vendyurskoe. It became clear that the ice-covered period length did not vary much from one winter to the other; however, a large difference was observed in the maximum average ice cover thickness and in the average water temperature at ice formation (e.g., larger thickness and colder water temperature during the 1995/96 winter).

scholarly journals Thermal regime of water courses of different order in the basin of the Upper Kolyma River

2018 ◽  
Vol 18 (4) ◽  
pp. 175-181
Author(s):  
Vladimir L. Samokhvalov ◽  
Nikolay V. Ukhov
Keyword(s):  
Water Temperature ◽  
Thermal Regime ◽  
River Mouth ◽  
Coarse Grained ◽  
Lower Section ◽  
Average Water Temperature ◽  
Area Of Interest ◽  
Average Water ◽  
Water Courses ◽  
Kolyma River

Evaluation of hydrological parameters and temperature regime of watercourses of various orders comes to the fore when studying the scientific problems of hydrobiology of watercourses and solving practical problems of development of fisheries and gold exploration in the regions of the Far North. This became particularly relevant due to a significant reduction in hydrological observations since the early 1990s. This article presents a quantitative investigation into the thermal regime of water courses and their spatial pattern. The paper focuses specifically studying the temperature and basic spatial parameters of streams and rivers in the area of interest. Statistical methods helped identify a close linkage between the temperature of water courses in the basin of the Upper Kolyma River and their respective sizes. A common trend has been found proving that the water temperature in the rivers increases downstream and with the increase in water course size, also known as order. A close correlation between the average water temperature, on the one hand, and the catchment area and water course length, on the other, is indicated by the relatively high correlation coefficients of 0.61 to 0.63 and 0.71 to 0.73, respectively. Average water temperatures in the summer and warm periods have been found to escalate with the increase of water course order from low (I and II) to high (VI–VII) by 4.7°C and 5.9°C, respectively, and in the Kolyma River – in the direction from the upper section (Orotuk village) to the lower section (the Korkodon River mouth) by 1.7°C and 2.1°C, respectively, even though the lower section of the river is located almost 2° north of the upper section. Due to the presence of perennial permafrost, river taliks have a cooling effect on the thermal regime of watercourses, so coolness occurs in sections of the river where there are favorable conditions for their formation. This is, first of all, the increased thickness of the well-permeable coarse-grained alluvium of the channel facies and open fracture zones in the bedrock.

scholarly journals Accelerating changes in ice mass within Greenland, and the ice sheet’s sensitivity to atmospheric forcing

2019 ◽  
Vol 116 (6) ◽  
pp. 1934-1939 ◽  
Author(s):  
Michael Bevis ◽  
Christopher Harig ◽  
Shfaqat A. Khan ◽  
Abel Brown ◽  
Frederik J. Simons ◽  
...  
Keyword(s):  
Global Positioning System ◽  
Climate Model ◽  
Regional Climate ◽  
Atmospheric Forcing ◽  
Surface Mass ◽  
The North ◽  
Global Positioning ◽  
The North Atlantic Oscillation ◽  
Gravity Recovery ◽  
Gps Observations

From early 2003 to mid-2013, the total mass of ice in Greenland declined at a progressively increasing rate. In mid-2013, an abrupt reversal occurred, and very little net ice loss occurred in the next 12–18 months. Gravity Recovery and Climate Experiment (GRACE) and global positioning system (GPS) observations reveal that the spatial patterns of the sustained acceleration and the abrupt deceleration in mass loss are similar. The strongest accelerations tracked the phase of the North Atlantic Oscillation (NAO). The negative phase of the NAO enhances summertime warming and insolation while reducing snowfall, especially in west Greenland, driving surface mass balance (SMB) more negative, as illustrated using the regional climate model MAR. The spatial pattern of accelerating mass changes reflects the geography of NAO-driven shifts in atmospheric forcing and the ice sheet’s sensitivity to that forcing. We infer that southwest Greenland will become a major future contributor to sea level rise.

Age, Growth, and Maturity of the Longnose Sucker Catostomus catostomus, of Western Lake Superior

1969 ◽  
Vol 26 (5) ◽  
pp. 1288-1298 ◽  
Author(s):  
Merryll M. Bailey
Keyword(s):  
Water Temperature ◽  
Lake Superior ◽  
Mature Female ◽  
Minimum Length ◽  
Age Group ◽  
Average Water Temperature ◽  
Group V ◽  
Western Lake ◽  
Average Water ◽  
Longnose Suckers

Studies of age, growth, and maturity were based on 1760 fish collected in western Lake Superior in 1964–65. The body:scale relation was curvilinear and the curve had an intercept of 1.65 inches on the length axis. The weight increased as the 2.85 power of the length. Some fish formed an annulus before May 18 in 1965; all had completed annuli by late September. Longnose suckers grew 3.6 inches the 1st year, reached 12 inches in the 6th year, and 18 inches in the 11th year. Fish from Pikes Bay grew faster than those from Gull Island Shoal. Over 6 years were required for weight to reach 1 lb and nearly 10 years to reach 2 lb. Minimum length at maturity was 10.5 inches for males and 11.5 inches for females. The youngest mature male belonged to age-group IV and the youngest mature female to age-group V. All males were mature at 14.5–14.9 inches (age-group VIII) and all females at 15.0–15.4 (age-group IX).Finclipped longnose suckers returned to spawn in the Brule River in successive years. One fish returned to spawn in 4 successive years. Many of the fish were not recaptured until 2 or 3 years after marking. The time of the Brule River spawning migration depended more on water temperature than on length of day. The average water temperature during the peak of the spawning runs of 1958–64 was 55.4 F. Larval suckers apparently spend little time in the Brule River and adjacent streams and drift downstream to the lake soon after hatching. The number of eggs in the ovaries of eight suckers ranged from 14 to 35 thousand and averaged 24 thousand for fish 13.9–17.7 inches long.

scholarly journals The GloSea4 Ensemble Prediction System for Seasonal Forecasting

2011 ◽  
Vol 139 (6) ◽  
pp. 1891-1910 ◽  
Author(s):  
Alberto Arribas ◽  
M. Glover ◽  
A. Maidens ◽  
K. Peterson ◽  
M. Gordon ◽  
...  
Keyword(s):  
Southern Oscillation ◽  
Regional Climate ◽  
Model Development ◽  
Seasonal Forecasting ◽  
Ensemble Prediction ◽  
Quasi Biennial Oscillation ◽  
Ensemble Prediction System ◽  
The North ◽  
Enso Teleconnections ◽  
The North Atlantic Oscillation

Abstract Seasonal forecasting systems, and related systems for decadal prediction, are crucial in the development of adaptation strategies to climate change. However, despite important achievements in this area in the last 10 years, significant levels of skill are only generally found over regions strongly connected with the El Niño–Southern Oscillation. With the aim of improving the skill of regional climate predictions in tropical and extratropical regions from intraseasonal to interannual time scales, a new Met Office global seasonal forecasting system (GloSea4) has been developed. This new system has been designed to be flexible and easy to upgrade so it can be fully integrated within the Met Office model development infrastructure. Overall, the analysis here shows an improvement of GloSea4 when compared to its predecessor. However, there are exceptions, such as the increased model biases that contribute to degrade the skill of Niño-3.4 SST forecasts starting in November. Global ENSO teleconnections and Madden–Julian oscillation anomalies are well represented in GloSea4. Remote forcings of the North Atlantic Oscillation by ENSO and the quasi-biennial oscillation are captured albeit the anomalies are weaker than those found in observations. Hindcast length issues and their implications for seasonal forecasting are also discussed.

scholarly journals Mid-to-late Holocene Temperature Evolution and Atmospheric Dynamics over Europe in Regional Model Simulations

2016 ◽  
Author(s):  
Emmanuele Russo ◽  
Ulrich Cubasch
Keyword(s):  
Late Holocene ◽  
Climate Models ◽  
Climate Model ◽  
Regional Climate ◽  
Climatic Conditions ◽  
Modes Of Variability ◽  
The North ◽  
Climate Reconstructions ◽  
The North Atlantic Oscillation ◽  
Almost All

Abstract. The improvement in resolution of climate models is always been mentioned as one of the most important factors when investigating past climatic conditions especially in order to evaluate and compare the results against proxy data. In this paper we present for the first time a set of high resolution simulations for different time slices of mid-to-late Holocene performed over Europe using a Regional Climate Model. Through a validation against a new pollen-based climate reconstructions dataset, covering almost all of Europe, we test the model performances for paleoclimatic applications and investigate the response of temperature to variations in the seasonal cycle of insolation, with the aim of clarifying earlier debated uncertainties, giving physically plausible interpretations of both the pollen data and the model results. The results reinforce previous findings showing that summertime temperatures were driven mainly by changes in insolation and that the model is too sensitive to such changes over Southern Europe, resulting in drier and warmer conditions. In winter, instead, the model does not reproduce correctly the same amplitude of changes, even if it captures the main pattern of the pollen dataset over most of the domain for the time periods under investigation. Through the analysis of variations in atmospheric circulation we suggest that, even though in some areas the discrepancies between the two datasets are most likely due to high pollen uncertanties, in general the model seems to underestimate the changes in the amplitude of the North Atlantic Oscillation, overestimating the contribution of secondary modes of variability

scholarly journals Water consumption when exposed to sun and shade for native goats in the semiarid of the State of Paraiba, Brazil

2012 ◽  
Vol 32 (1) ◽  
pp. 21-29
Author(s):  
Dermeval A. Furtado ◽  
Jackson R. de S. Leite ◽  
Jose W. B. do Nascimento ◽  
Antonio F. Leal ◽  
Andrea S. Silva
Keyword(s):  
Body Weight ◽  
Water Temperature ◽  
Water Consumption ◽  
The Other ◽  
Average Weight ◽  
The Sun ◽  
Average Water Temperature ◽  
Average Water ◽  
Sun And Shade ◽  
Average Consumption

This work aimed to evaluate the preference and water consumption of native goats in the semiarid of Brazil. The water was freely supplied, in individual buckets, one exposed to the sun and the other in the shade. The experiment was realized using 18 animals of Moxotó, Graúna and Azul breeds, with average weight of 16,6 ± 2,4 kg, kept in confinement in individual stalls equipped with feeders and drinkers, during the period from January to February of 2009. The water temperature was measured by sensors (thermocouples type T - copper/constantan), which were coupled to a system of data acquisition. It was observed that the average water temperature exposed to the sun was 29.02 ºC, and 23.85 ºC in the shade. For all breeds there was a preference for the water exposed to the sun, corresponding to an average consumption of 64.71% of the total. Among the breeds, the greatest preference for water exposed to the sun was the Azul (71.18%), followed by the Moxotó (65.95%) and the Graúna (57.00%). The animals consumed more water during the day, and the average water consumption was 1.15 grams day-1, corresponding to 6.9 % of body weight of the animals.

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