This dataset contains raster image files in support of the conclusions published in "Water use demand in Mediterranean California under multiple scenarios of developed and agricultural land use " in the journal PLOS One. We used the USGS's LUCAS model to examine a broad suite of spatially explicit future land use scenarios and their associated county-level water use demand, including the historical (1992-2011) and projected periods (2012-2062) across 40 Monte Carlo simulations.We examined a range of potential water demand futures sampled from a 20-year record of historical (1992-2012) data to develop a suite of potential future land change scenarios from 2012-2062. These scenario simulations include a 1) business-as-usual (BAU), 2) low agriculture (LA), 3) high agriculture (HA), 4) low urban (LU), 5) high urban (HU), 6) lowest of the low (LL), and 7) highest of the high (HH) anthropogenic use scenarios.

California Water Code Section 10004.6 requires the California Department of Water Resources (DWR) to quantify current and future water conditions in the state. This information is published in the California Water Plan (Water Plan), which is updated every five years. Water Plan Updates 2005, 2009, 2013, 2018 and 2023 have progressively developed a Water Evaluation And Planning (WEAP) model for assessing the impacts of climate change on California water resources and infrastructure, as well as the adaptation strategies needed and available to improve regional water resilience. Update 2023 brought significant improvements to input data and process in the model as described in the model documentation provided in the resources. The current WEAP model is called the WEAP-CVPA model as it covers the Central Valley of California at the planning area scale. The model was run on WEAP version 2021.0.2.2 but is compatible with newer versions of WEAP based on limited testing. Included in this dataset is: * The model itself with input files provided as a zip file * A link to SEI’s website where the software to run and view the model can be downloaded * The documentation for the model that was released as part of the California Water Plan Update 2023 * 4 CSVs with the post processed data from the study that were used to create the Future Scenarios Interactive Data Explorer, separated by summary vs detailed response surface as well as by planning area metrics vs points of interest metrics * A link to the Future Scenarios Interactive Data Explorer where the post processed results and response surfaces available at the planning area level * The raw exports from the model of the level 2070 that were post processed to create the data that informed the Water Plan Update 2023 * Spatial Boundaries for Water Plan Planning Areas which were used as the basis for spatial areas in the WEAP model

LUCAS-W is a scenario-based simulation model of coupled land use change and associated water demand for California's Central Coast region from 2001-2061. The model is a verison of the LUCAS model, which uses the SyncroSim software framework (Software documentation available at http://doc.syncrosim.com/index.php?title=Reference_Guide), that contains a new coupling with statistical software R (https://www.r-project.org/) to enable dynamic feedbacks between land-use change, resulting water demand, and water availability. The model was parameterized with land-use change and water use empirically estimated from county-scale historic data, as well as results from dozens of local agencies’ groundwater modeling efforts. It was used to assess a set of five stakeholder-driven scenarios that explored alternative development pathways assuming the continuation of historic land use change rates but with different intensities of water supply and land-use management. Water management strategies were (1) water demand limits, and (2) water supply enhancement, while land use management strategies were (3) urban sprawl limits on recharge areas and prime farmland, and (4) preservation of priority habitat areas. By scaling up studies of local-scale diverse, heterogeneous aquifers and management approaches to a regional level, the model can enable a projection of spatial changes due to shifts in LULC and water management including leakage from land and water use regulated areas into unregulated areas, information that is key to future agency planning for sustainability. The resulting land-use projections provide a range of development projections under different sets of management assumptions: patterns of development that do not stabilize “business-as-usual” (WL), assume that water demand stabilizes at a range of possible sustainable water supply levels (MM, WH), and that assume a relatively unregulated (LL) or tightly compact (LH) pattern of future development. See Van Schmidt et al. (2022) Journal of Hydrology: Regional Studies (https://doi.org/10.1016/j.ejrh.2022.101056) for more details.

Tabular data output from a series of groundwater modeling simulations for five counties along the Central Coast of California, USA. We used a spatially explicit state-and-transition simulation model with stocks and flows that integrates climate, land-use change, human water use, and groundwater gain-loss to examine the impact of future climate and land use change on groundwater balance and water demand at 270-m resolution from 2010 to 2060. The model incorporated downscaled groundwater recharge projections based on a Warm/Wet and a Hot/Dry climate future using output from the Basin Characterization Model, a spatially explicit hydrological process-based model. Two urbanization projections from a parcel-based, regional urban growth model representing 1) recent historical and 2) state-mandated housing growth projections were used as alternative spatial targets for future urban growth. Agricultural projections were based on recent historical trends from remote sensing data. Annual projected changes in groundwater balance were calculated as the difference between land-use related water demand, based on historical estimates, and climate-driven recharge plus agriculture return flows to groundwater from excess irrigation. For each combination of the two climate and two land-use change scenarios, we ran 50 Monte Carlo realizations of the model. Results presented here have been aggregated from the individual cell level and summarized by county.

This data release provides the resulting land-use projections for California's Central Coast from 2001-2061 at a resolution of 270-m. Data are provided as (1) annual rasters and (2) summarized as the mean annual transition probability across 10 Monte Carlo iterations. Each package contains folders for five scenarios, which have different sets of management assumptions along two axes: Water management Low/Moderate/High and Land use management Low/Moderate/High. - MM (Moderate/Moderate): a scenario where water demand caps reduce development in overdrafted groundwater basins based on current total water supplies, and where prime farmland and groundwater recharge areas will be protected from urban sprawl (i.e., land use projections assuming development stabilizes at a level sustainable with current water supplies, and urban sprawl limits). The other four scenarios differ from the MM scenario by altering one of these management strategies, while keeping the second strategy at the "Moderate" level. - WL (Water management Low): a scenario with no feedbacks between water supplies and development (i.e., land use projections assuming development is not constrained by water availability, closest to a "business-as-usual" continuation of the region's historic trajectory). - WH (Water management High): a scenario that assumes that water demand caps, but with increased caps due to enhanced water supplies proposed under local groundwater agencies' Groundwater Sustainability Plans (i.e., land use projections assuming development stabilizes at a higher water demand). - LL (Land use management Low): a scenario where prime farmland and groundwater recharge areas are not protected from urban sprawl (i.e., land use projections assuming relatively unregulated land use planning, with water sustainability based on current supplies). - LH (Land use management High): a scenario where almost all the state's priority habitats are preserved from urbanization or agricultural expansion (i.e., land use projections assuming a very compact pattern of development, with water sustainability based on current supplies). These projections were created with LUCAS-W, a scenario-based simulation model of coupled land use change and associated water demand. This model is a version of the LUCAS model, which uses the SyncroSim software framework (Software documentation available at http://doc.syncrosim.com/index.php?title=Reference_Guide), that contains a new coupling with statistical software R (https://www.r-project.org/) to enable dynamic feedbacks between land-use change, resulting water demand, and water availability. The model was parameterized with land-use change and water use empirically estimated from county-scale historic data, as well as results from dozens of local agencies’ groundwater modeling efforts. By scaling up studies of local-scale diverse, heterogeneous aquifers and management approaches to a regional level, the model can enable a projection of spatial changes due to shifts in LULC and water management including leakage from land and water use regulated areas into unregulated areas, information that is key to future agency planning for sustainability. See Van Schmidt et al. (2021) Water Resources Research (doi: XXXXXXXXXXXXX) for more details.

This dataset consists of modeled projections of land use and land cover and population for the State of California for the period 1970-2101. For the 1970-2001 period, we used the USGS's LUCAS model to "backcast" LULC, beginning with the 2001 initial conditions and ending with 1970. For future projections, the model was initialized in 2001 and run forward on an annual time step to 2100. In total 5 simulations were run with 10 Monte Carlo replications of each simulation. The simulations include: 1) Historical backcast from 2001-1970, 2) Business-as-usual (BAU) projection from 2001-2101, and 3) three modified BAU projections based on California Department of Finance population projections based on high, medium, and low growth rates.

Seamless unconfined groundwater heads for coastal California groundwater systems were modeled with homogeneous, steady-state MODFLOW simulations. The geographic extent examined was limited primarily to low-elevation (i.e. land surface less than approximately 10 m above mean sea level) areas. In areas where coastal elevations increase rapidly (e.g., bluff stretches), the model boundary was set approximately 1 kilometer inland of the present-day shoreline. Steady-state MODFLOW groundwater flow models were used to obtain detailed (10-meter-scale) predictions over large geographic scales (100s of kilometers) of groundwater heads for both current and future sea-level rise (SLR) scenarios (0 to 2 meters (m) in 0.25 m increments, 2.5 m, 3 m, and 5 m) using a range of horizontal hydraulic conductivity (Kh) scenarios (0.1, 1, and 10 m/day). For each SLR/Kh combination, results are provided for two marine boundary conditions, local mean sea level (LMSL) and mean higher-high water (MHHW), and two model versions. In the first model version, groundwater reaching the land surface is removed from the model, simulating loss via natural drainage. In the second model version, groundwater reaching the land surface is retained, simulating the worst-case "linear" response of groundwater head to sea-level rise. Additional details about the groundwater model and data sources are outlined in Befus and others (2020) and in Groundwater_model_methods.pdf (available at https://www.sciencebase.gov/catalog/file/get/5b8ef008e4b0702d0e7ec72b?name=Groundwater_model_methods.pdf). Methods specific to groundwater head and water table depth products are outlined in Groundwater_head_and_water_table_depth_methods.pdf (available at https://www.sciencebase.gov/catalog/file/get/5bda1563e4b0b3fc5cec39b4?name=Groundwater_head _and_water_table_depth_methods.pdf). Please read the model details, data sources and methods summaries and inspect model output carefully. Data are complete for the information presented. Users should note that while the metadata Spatial Reference Information/UTM Zone Number in this document is 10, some files in southern California are in UTM Zone 11, as noted in the Format Specification for individual downloadable files. As a result users may need to modify the metadata for automated import and display of Zone 11 datafiles.

To support coordinated conservation, wetland restoration, and climate adaptation planning, we have developed five future scenarios of the Central Valley's seasonally flooded cropland and wetland waterbird habitat based on the State’s most recent climate and land use projections (Wilson et al. 2021).The USGS Western Geographic Science Center and Point Blue Conservation Science modeled a Business-as-Usual scenario plus the four scenarios developed for the Central Valley Landscape Conservation Project, which diverged along two key themes: water availability and management for conservation. Scenarios varied by climate projection (hot and wet vs. warm and dry) and management priorities (wetland restoration rate, crop conversion rate, and prioritization of water for wetland and cropland habitats). Urbanization rates were the same for all scenarios. To model these scenarios, we integrated a hydrologic and water-use model (the Water Evaluation and Planning (WEAP) model, WEAP-CVwh, Matchett and Fleskes, 2017) with a land change model (the Land Use and Carbon Scenario Simulator, LUCAS, Wilson et al. 2020). The models produced annual maps of land use change and monthly maps of flooded habitat probability at 270-meter resolution, from 2011 to 2101 (Wilson et al. 2021). The scenarios were: Historical Business As Usual (HBAU) = historical water availability, historical management California Dreamin' (DREAM) = high water, good management Bad Business As Usual (BBAU) = high water, poor management Everyone Equally Miserable (EEM) = low water, good management Central Valley Dustbowl (DUST) = low water, poor management This data release contains three types of model output tabular summaries for four geographic areas: WEAP model zones, Sustainable Groundwater Management Act (SGMA) California Bulletin 118 groundwater sub-basins, Central Valley Joint Venture (CVJV) planning basins, and Central Valley regions. The datasets summarize 1) land use change for select land use/land cover classes, 2) area of likely flooded habitat, and 3) change in January flooded habitat area and its causes for the 5 future scenarios of managed waterbird habitat. The datasets were generated from the LUCAS model and the WEAP CVwh model as described in the parent manuscript. The full methods and results of this research are described in detail in the parent manuscript "Integrated modeling of climate and land change impacts on future dynamic wetland habitat – a case study from California’s Central Valley" (2021). These tabular summaries provide the underlying data behind the figures in the ESRI Story Map: Central Valley Water and Land Use Futures, https://wim.usgs.gov/geonarrative/centralvalleyfutures/ (Moritsch et al. 2021).