Towards scale independent lake-hydrology modeling in semi-arid regions: mHM lake module (mLM) development.

\documentclass{article}\usepackage[utf8]{inputenc}\begin{document}\noindent \Large{Towards scale independent lake-hydrology modeling in semi-arid regions: mHM lake module (mLM) development}\\\medskip \\\noindent \normalsize{Shrestha PK$^{1,*}$, Samaniego L$^{1}$, Thober S$^{1}$, Kumar R$^{1}$}, Behnia S$^{2}$, Rakovec O$^{1}$\\\noindent $^1$ UFZ -- Helmholtz Center for Environmental Research, Leipzig, Germany\\\noindent $^2$ Institute of Geodesy, University of Stuttgart, Stuttgart, Germany\\\noindent $^*$ pallav-kumar.shrestha@ufz.de\\\noindent With large fluctuations in annual precipitation, one of thekey anthropogenic features of semi-arid regions is seasonal storage andits intensive use of water. A reliable hydrological forecast system atsuch regions requires accurate representation of the existing lakesand/or hydraulic regulation infrastructures. The meso-scale hydrologicalmodel (mHM), a well established scale-independent hydrological model,was augmented with a new lake module for tacking this task.The mHM lake module (mLM) delineates natural or man-made lakes(reservoirs) based on the fine morphology input ($\ell_0$, 0.2 --1\,km). Lake precipitation and evaporation are calculated using thecoarse meteorology input ($\ell_2$, 10 -- 50\,km) while lake inflow iscollected from adjoining mHM cells (hydrology level, $\ell_1$, 1 --10\,km). Apart from these lake processes, seepage, spill and reservoirregulation are calculated and the balanced outflow is passed on to therouting module further downstream. Most of the lake process parametersare regionalized (as other mHM parameters) while others are optimizedbased on a user-given input range. The user also has the option tooptimize the mLM parameters using reservoir levels, spill history and/ordischarge gauges. As a part of the Seasonal Water Management (SaWaM)project (Funded by the BMBF), the headwater catchment of S\~ao Franciscobasin (Brazil) is selected as test case for development phase. Lakelevels based on satellite altimetry are used during modelcalibration. The results highlights the significant model improvementachieved by accounting process based storage effect in lake-hydrologysystems.Apart from the successful integration of mLM into the routing system ofmHM, this study discusses future plans such as evolving mLM to catercascade lake-hydrology systems and dynamic reservoir storage conditionsdue to sedimentation and sluicing. Furthermore, it aims to exploreconcepts for scale free modeling of lake-hydrology systems, upholdingthe multi-scale paradigm of mHM.\end{document} [ABSTRACT FROM AUTHOR]