Effect of climate warming on lake thermal and dissolved oxygen stratifications: A review

Climate warming has many complex, profound direct and indirect effects on lake physical, chemical, biological processes, and ecosystem. Overall, the response of individual lake to climate change can be very different and shows a great regional difference. Climate warming alters lake thermal and dissolved oxygen stratifications to further affect lake biological processes, and the structure and function of lake ecosystem. This study detailedly reviews the study progresses of this field including lake warming trend, the effects of the long-term slowly rising air temperatures and the extreme heat wave on lake thermal and dissolved oxygen stratifications, and the projected climate scenarios. Many studies show the lake warming with the different slopes is recorded for the globally different regions lakes. The long-term slowly rising air temperatures and the extreme heat wave will result in the earlier onset of stratification, the late mixing and an increase in the length of the thermal stratification duration. In addition, lake warming will cause the descreases of mixing depth and thermocline depth, and the increase of lake thermal stability. Correspondingly, the diffusion depth of dissolved oxygen and oxycline depth significantly decrease, which will aggravate the hypoxic and anoxic environment of lake bottom. In addition, climate warming has some indirect effects on lake thermal and dissolved oxygen stratifications through changing the rainfall, input substances of the catchment, and wind speed. Therefore, much work is needed in many research areas including experimental data evidence, empirical and numerical model to validate and predict the potential effects of climate warming on lake thermal and dissolved oxygen stratifications. ©, 2015, China Water Power Press. All right reserved.