Uncertainty in projections of future lake thermal dynamics is differentially driven by lake and global climate models

PeerJ

article

Jacob H. Wynne¹  Whitney Woelmer¹  Tadhg N. Moore¹  R. Quinn Thomas¹  Kathleen C. Weathers⁴  Cayelan C. Carey¹ 

[1] Department of Biological Sciences, Virginia Polytechnic Institute and State University;Department of Microbiology, Oregon State University;Department of Forest Resources and Environmental Conservation, Virginia Polytechnic Institute and State University;Cary Institute of Ecosystem Studies

关键词: Ecosystem modeling;    Uncertainty;    Lake thermal dynamics;    Climate change;    Scenarios;    Hydrodynamics;    Process-based models;    Lake models;    Ensemble modeling;    Management;   

DOI  :  10.7717/peerj.15445

学科分类：社会科学、人文和艺术（综合）

来源: Inra

【 摘 要 】

Freshwater ecosystems provide vital services, yet are facing increasing risks from global change. In particular, lake thermal dynamics have been altered around the world as a result of climate change, necessitating a predictive understanding of how climate will continue to alter lakes in the future as well as the associated uncertainty in these predictions. Numerous sources of uncertainty affect projections of future lake conditions but few are quantified, limiting the use of lake modeling projections as management tools. To quantify and evaluate the effects of two potentially important sources of uncertainty, lake model selection uncertainty and climate model selection uncertainty, we developed ensemble projections of lake thermal dynamics for a dimictic lake in New Hampshire, USA (Lake Sunapee). Our ensemble projections used four different climate models as inputs to five vertical one-dimensional (1-D) hydrodynamic lake models under three different climate change scenarios to simulate thermal metrics from 2006 to 2099. We found that almost all the lake thermal metrics modeled (surface water temperature, bottom water temperature, Schmidt stability, stratification duration, and ice cover, but not thermocline depth) are projected to change over the next century. Importantly, we found that the dominant source of uncertainty varied among the thermal metrics, as thermal metrics associated with the surface waters (surface water temperature, total ice duration) were driven primarily by climate model selection uncertainty, while metrics associated with deeper depths (bottom water temperature, stratification duration) were dominated by lake model selection uncertainty. Consequently, our results indicate that researchers generating projections of lake bottom water metrics should prioritize including multiple lake models for best capturing projection uncertainty, while those focusing on lake surface metrics should prioritize including multiple climate models. Overall, our ensemble modeling study reveals important information on how climate change will affect lake thermal properties, and also provides some of the first analyses on how climate model selection uncertainty and lake model selection uncertainty interact to affect projections of future lake dynamics.

【 授权许可】

CC BY