CT: Climate Type; A: Area (km2); ASL: elevation above
sea level (m); T: Annual average night temperature of lake waters (°C).
3.4.2. Lake area versus lake depth
Area, depth and volume of lakes have strong impact on LWST (Figure 3,
Table 1). Of the lakes investigated, Lake Tonlesap (Cambodia) exhibited
the highest temperature (max: 26.87°C); it is the shallowest of the
lakes (around 12 m deep) and is located at the lowest elevation (4 m)
(Table 2). A previous study has suggested that the annual heat budget of
lakes is strongly dependent on mean depth because a deeper water column
corresponds to a larger heat storage capacity (Gorham, 1964). That study
further indicated a strong relationship between heat budget and lake
water volume (semi-logarithmic scale) (Gorham, 1964). For deep and large
lakes, more energy is needed to raise lake water temperature by one
unit. Thus, less temporal variation in LWST was observed with the very
large lakes, e.g., Baikal, Onega and Issyk (Figure 4 and Figure 5; Table
1). A similar line of reasoning can be advanced to explain the lower DTD
values for lakes with large water volume. Lake Baikal showed slightly
higher variability and DTDs than Lake Van (Eastern Turkey), but the
difference was insignificant. Besides water volume, other factors (e.g.,
the ratio of area to mean depth, and shoreline characteristics) may have
contributed to difference in LWST variability and DTDs (Leblanc,
Akbarzadeh, Andrews, Lu, & Golding, 2011), and future investigations
should determine the extent of these contributions.
Table 2: Information about selected typical large Eurasia lakes