Status and progress in global lake database developments

Lakes affect local weather and climate. This influence should be taken into account in NWP models through parameterization. For the atmospheric simulation, global coverage of lake depth data is essential. To provide such data Global Lake Database (GLDB) has been created. GLDB contains information about lake location (latitude, longitude), water surface area, and lake mean and max depths. The mean depth is provided as a gridded data set.</p

Amplified surface temperature response of cold, deep lakes to inter-annual air temperature variability

Summer lake surface water temperatures (LSWTs) have previously been shown to respond more rapidly to climatic warming compared to local summer surface air temperatures (SATs). In a global- scale analysis, we explore the factors underpinning the observation of an amplified response of summer LSWT to SAT variability using 20 years of satellite-derived temperatures from 144 lakes. We demonstrate that the degree of amplification in inter-annual summer LSWT is variable, and is greater for cold lakes (e.g. high latitude and high altitude), which are characterised by a short warming season, and deep lakes, that exhibit long correlation timescales of temperature anomalies due to increased thermal inertia. Such lakes are more likely to display responses in excess of local inter-annual summer SAT variability. Climatic modification of LSWT has numerous consequences for water quality and lake ecosystems, so quantifying this amplified response at a global scale is important

Attribution of global lake systems change to anthropogenic forcing

Lake ecosystems are jeopardized by the impacts of climate change on ice seasonality and water temperatures. Yet historical simulations have not been used to formally attribute changes in lake ice and temperature to anthropogenic drivers. In addition, future projections of these properties are limited to individual lakes or global simulations from single lake models. Here we uncover the human imprint on lakes worldwide using hindcasts and projections from five lake models. Reanalysed trends in lake temperature and ice cover in recent decades are extremely unlikely to be explained by pre-industrial climate variability alone. Ice-cover trends in reanalysis are consistent with lake model simulations under historical conditions, providing attribution of lake changes to anthropogenic climate change. Moreover, lake temperature, ice thickness and duration scale robustly with global mean air temperature across future climate scenarios (+0.9 °C °Cair–1, –0.033 m °Cair–1 and –9.7 d °Cair–1, respectively). These impacts would profoundly alter the functioning of lake ecosystems and the services they provide

Estimation of the mean depth of boreal lakes for use in numerical weather prediction and climate modelling

ISI Document Delivery No.: AD7AA Times Cited: 0 Cited Reference Count: 21 Cited References: Amante C, 2009, NGDC24 NOAA NESDIS, V24, P1 Balsamo G, 2010, BOREAL ENVIRON RES, V15, P178 CANFIELD DE, 1985, J AQUAT PLANT MANAGE, V23, P25 Champeaux JL, 2004, INT GEOSCI REMOTE SE, P2046 Doganovsky A., 2006, P C 59 HERZ READ GEO, P15 Doganovsky A., 2012, LIMNOL REV 2012, V12, P11, DOI [10.2478/v10194-011-0040-2, DOI 10.2478/V10194-011-0040-2] Eerola K, 2010, BOREAL ENVIRON RES, V15, P130 Hormann K, 2001, COMP GEOM-THEOR APPL, V20, P131, DOI 10.1016/S0925-7721(01)00012-8 Kitaev S., 1984, ECOLOGICAL BASIS LAK, V208 Kondratiev S., 2010, THESIS SAINT PETERSB, P51 Kourzeneva E, 2012, TELLUS A, V64, DOI 10.3402/tellusa.v64i0.15640 Kourzeneva E., 2009, ALADIN NEWSLETTER, V37, P46 Kourzeneva E, 2012, TELLUS A, V64, DOI 10.3402/tellusa.v64i0.17226 Lee R. W., 1997, LIGHT ATTENUATION SH, P97 Mironov D, 2008, PARAMETERIZATION LAK, V11, P41 PGAW (Physical Geography Atlas of the World), 1964, PGAW PHYS GEOGR ATL Samuelsson P, 2010, BOREAL ENVIRON RES, V15, P113 SAW (Small Atlas of the World), 1990, SAW SMALL ATL WORLD Sheffield J, 2006, J CLIMATE, V19, P3088, DOI 10.1175/JCLI3790.1 Tranvik LJ, 2009, LIMNOL OCEANOGR, V54, P2298, DOI 10.4319/lo.2009.54.6_part_2.2298 Walter KM, 2007, PHILOS T R SOC A, V365, P1657, DOI 10.1098/rsta.2007.2036 Choulga, Margarita Kourzeneva, Ekaterina Zakharova, Elena Doganovsky, Arkady Zakharova, Elena/N-7731-2013 Zakharova, Elena/0000-0002-2962-1439 ECMWF The authors thank Yurii Batrak and Suleiman Mostamandi (Russian State Hydrometeorological University), as well as Pavel Andreev (North-West Interregional Territorial Department of the Federal Service for Hydrometeorology and Environmental Monitoring) for useful tips and discussions. Two anonymous reviewers made many useful comments. The project was made possible due to the support from ECMWF. 0 CO-ACTION PUBLISHING JARFALLA TELLUS ALakes influence the structure of the atmospheric boundary layer and, consequently, the local weather and local climate. Their influence should be taken into account in the numerical weather prediction (NWP) and climate models through parameterisation. For parameterisation, data on lake characteristics external to the model are also needed. The most important parameter is the lake depth. Global database of lake depth GLDB (Global Lake Database) is developed to parameterise lakes in NWP and climate modelling. The main purpose of the study is to upgrade GLDB by use of indirect estimates of the mean depth for lakes in boreal zone, depending on their geological origin. For this, Tectonic Plates Map, geological, geomorphologic maps and the map of Quaternary deposits were used. Data from maps were processed by an innovative algorithm, resulting in 141 geological regions where lakes were considered to be of kindred origin. To obtain a typical mean lake depth for each of the selected regions, statistics from GLDB were gained and analysed. The main result of the study is a new version of GLDB with estimations of the typical mean lake depth included. Potential users of the product are NWP and climate models

ERA5-Land: a state-of-the-art global reanalysis dataset for land applications

International audienceFramed within the Copernicus Climate Change Service (C3S) of the European Commission, the European Centre for Medium-Range Weather Forecasts (ECMWF) is producing an enhanced global dataset for the land component of the fifth generation of European ReAnalysis (ERA5), hereafter referred to as ERA5-Land. Once completed, the period covered will span from 1950 to the present, with continuous updates to support land monitoring applications. ERA5-Land describes the evolution of the water and energy cycles over land in a consistent manner over the production period, which, among others, could be used to analyse trends and anomalies. This is achieved through global high-resolution numerical integrations of the ECMWF land surface model driven by the downscaled meteorological forcing from the ERA5 climate reanalysis, including an elevation correction for the thermodynamic near-surface state. ERA5-Land shares with ERA5 most of the parameterizations that guarantees the use of the state-of-the-art land surface modelling applied to numerical weather prediction (NWP) models. A main advantage of ERA5-Land compared to ERA5 and the older ERA-Interim is the horizontal resolution, which is enhanced globally to 9 km compared to 31 km (ERA5) or 80 km (ERA-Interim), whereas the temporal resolution is hourly as in ERA5. Evaluation against independent in situ observations and global model or satellite-based reference datasets shows the added value of ERA5-Land in the description of the hydrological cycle, in particular with enhanced soil moisture and lake description, and an overall better agreement of river discharge estimations with available observations. However, ERA5-Land snow depth fields present a mixed performance when compared to those of ERA5, depending on geographical location and altitude. The description of the energy cycle shows comparable results with ERA5. Nevertheless, ERA5-Land reduces the global averaged root mean square error of the skin temperature, taking as reference MODIS data, mainly due to the contribution of coastal points where spatial resolution is important. Since January 2020, the ERA5-Land period available has extended from January 1981 to the near present, with a 2- to 3-month delay with respect to real time. The segment prior to 1981 is in production, aiming for a release of the whole dataset in summer/autumn 2021. The high spatial and temporal resolution of ERA5-Land, its extended period, and the consistency of the fields produced makes it a valuable dataset to support hydrological studies, to initialize NWP and climate models, and to support diverse applications dealing with water resource, land, and environmental management. The full ERA5-Land hourly (Muñoz-Sabater, 2019a) and monthly (Muñoz-Sabater, 2019b) averaged datasets presented in this paper are available through the C3S Climate Data Store at https://doi.org/10.24381/cds.e2161bac and https://doi.org/10.24381/cds.68d2bb30, respectively

Attribution of global lake systems change to anthropogenic forcing

Lake ecosystems are jeopardized by the impacts of climate change on ice seasonality and water temperatures. Yet historical simulations have not been used to formally attribute changes in lake ice and temperature to anthropogenic drivers. In addition, future projections of these properties are limited to individual lakes or global simulations from single lake models. Here we uncover the human imprint on lakes worldwide using hindcasts and projections from five lake models. Reanalysed trends in lake temperature and ice cover in recent decades are extremely unlikely to be explained by pre-industrial climate variability alone. Ice-cover trends in reanalysis are consistent with lake model simulations under historical conditions, providing attribution of lake changes to anthropogenic climate change. Moreover, lake temperature, ice thickness and duration scale robustly with global mean air temperature across future climate scenarios (+0.9 °C °Cair–1, –0.033 m °Cair–1 and –9.7 d °Cair–1, respectively). These impacts would profoundly alter the functioning of lake ecosystems and the services they provide