Estimation of Water Temperature of Large Lakes in Cold Climate Regions during the Period of Strong Coupling between Water and Air Temperature Fluctuations

Abstract

Near-surface bulk water temperature measured in large northern lakes during the warm season with buoys can be characterized by three components: a slowly varying seasonal-/climate-related trend, fluctuations at the time scale of weather perturbations, and rapid daily fluctuations. When thermal infrared data are used to estimate surface water temperature, an additional term relating the differences between the skin and bulk temperatures is implied. Buoy data in this work serve to demonstrate the existence of a period of strong signal coupling between fluctuations of water temperature and air temperature. The period of strong signal coupling does not extend beyond the date of maximum temperature in the water temperature trend. During this period, a simple linear transformation of air temperature fluctuations can be used to simulate the buoy water temperature fluctuations. Attempts to simulate water temperature fluctuations from air temperature alone are not possible beyond this period. Water temperature simulation error depends on the distance of the air temperature measurement from the buoy, ranging from Ϯ1.1°C at 0 km to Ϯ1.4°C at 40 km. The method developed with buoy data is applied to the combination of satellite thermal infrared and operationally measured air temperature data to simulate water temperatures. Through the use of satellite data, the water temperature simulations are extended beyond the period of strong coupling.

Modelling hourly rates of evaporation from small lakes

“…For the three study seasons, the average evaporation rate during the cooling period was 3.05 mm/d. This pattern of temperatures was also demonstrated by Bussières and Granger (2007), who derived seasonal curves of water temperature for large lakes and suggested that these will have an effect on the evaporation rates. Figure 5 shows the cumulative seasonal evaporation, net radiation and turbulent heat exchange rates, and the temperature contrast between the lake and adjacent land surfaces at Landing Lake for the 2007 open water period.…”

Controls on open water evaporation

“…For the three study seasons, the average evaporation rate during the cooling period was 3.05 mm/d. This pattern of temperatures was also demonstrated by Bussières and Granger (2007), who derived seasonal curves of water temperature for large lakes and suggested that these will have an effect on the evaporation rates. Figure 6 shows the seasonal evaporation, radiation and turbulent heat exchange 25 rates and the temperature contrast between the water and adjacent land surfaces at Landing Lake for the 2007 open water period.…”

Diversity in the origins of proteostasis networks — a driver for protein function in evolution

“…The loss of the heat shock response in Antarctic marine animals is easily explained in terms of their environment: the extraordinarily stable temperature in the Southern Ocean makes a heat shock response superfluous (although perhaps not inconsequential to artic ecology as a consequence of ongoing climate change). This explanation does not, however, apply to Hydra oligactis , as temperature variations at the surfaces of lakes where this organism lives are much greater 87 . It does, however, raise the possibility that this species lacks a heat shock response either because it evolved a temperature-resistant proteome or because responding to the temperature fluctuations that it experiences has a maladaptive effect on survival and fitness in its particular niche, as could be the case in prolonged chronic stress diseases in humans.…”