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In 1969, researchers developed the first global circulation model (Ruttiman 2006); however, it was not until 2014 that modelers first attempted a global ecosystem and biodiversity model that included human pressures (i.e., the Madingley Model) (Harfoot et al. 2014). Other large-scale models of biodiversity exist, such as GLOBIO (Alkemade et al. 2009), but to date there are no well accepted global biodiversity models similar to global circulation models that can help guide global biodiversity policy development and targets. The lack of global biodiversity models compared to the extensive array of general circulation models provides a unique opportunity for climate, ecosystem, and biodiversity modeling experts to...
Abstract (from AGU 100): This study investigates snowmelt and streamflow responses to cloudiness variability across the mountainous parts of the western United States. Twenty years (1996–2015) of Geostationary Operational Environmental Satellite‐derived cloud cover indices (CC) with 4‐km spatial and daily temporal resolutions are used as a proxy for cloudiness. The primary driver of nonseasonal fluctuations in daily mean solar insolation is the fluctuating cloudiness. We find that CC fluctuations are related to snowmelt and snow‐fed streamflow fluctuations, to some extent (correlations of <0.5). Multivariate linear regression models of daily snowmelt (MELT) and streamflow (ΔQ) variations are constructed for each...
Abstract (from http://www.bioone.org/doi/abs/10.3417/2017006): The Earth system is undergoing rapid, profound anthropogenic change. The primary axes of change include not only the climate system, but also the spread of invasive species, altered biogeochemical and hydrological cycles, modified disturbance regimes, and land degradation and conversion. These factors are influencing the distribution of species and the structure and function of ecosystems worldwide, interacting with climatic stressors that may preclude the persistence of many current species distributions and communities. Ecological disturbances such as wildfires and insect outbreaks can interact with climate variability to precipitate abrupt change...
Future changes in the number of dry days per year can either reinforce or counteract projected increases in daily precipitation intensity as the climate warms. We analyze climate model projected changes in the number of dry days using 28 coupled global climate models from the Coupled Model Intercomparison Project, version 5 (CMIP5). We find that the Mediterranean Sea region, parts of Central and South America, and western Indonesia could experience up to 30 more dry days per year by the end of this century. We illustrate how changes in the number of dry days and the precipitation intensity on precipitating days combine to produce changes in annual precipitation, and show that over much of the subtropics the change...
Exposure (vulnerability) index for the future time period (2061-2080) representing projected climate conditions from the Meteorological Research Institute's Coupled Atmosphere-Ocean General Circulation Model, version 3, and the rcp85 emissions scenario. The exposure model uses LANDFIRE vegetation data and Worldclim climate data .The raster values represent exposure scores for the corresponding vegetation type. The modeled vegetation types can be spatially associated with the exposure values by overlaying them with the "landfire_veg_sw_300m.tif" raster.Exposure values represent where the location falls in climate space relative to its recent historical distribution:5 (core 5% of historical climate space); 10 (5 -...
A new method for automatic detection of atmospheric rivers (ARs) is developed and applied to an atmospheric reanalysis, yielding an extensive catalog of ARs land-falling along the west coast of North America during 1948–2017. This catalog provides a large array of variables that can be used to examine AR cases and their climate-scale variability in exceptional detail. The new record of AR activity, as presented, validated and examined here, provides a perspective on the seasonal cycle and the interannual-interdecadal variability of AR activity affecting the hydroclimate of western North America. Importantly, AR intensity does not exactly follow the climatological pattern of AR frequency. Strong links to hydroclimate...
This code computes the analytical solution for the damping of sinusoidal infiltration in variably saturated soils described by Bakker and Neiber (2009) and implemented by Dickinson et al. (2014). The usage of the code is documented in the appendix of Dickinson et al. (2014). Bakker, M., Nieber, J.L., 2009. Damping of sinusoidal surface flux fluctuations with soil depth. Vadose Zone J. 8, 119–126,http://dx.doi.org/10.2136/vzj2008.0084. Dickinson, J.E., Ferré, T.P.A., Bakker, M., Crompton, B., 2014. A screening tool for delineating subregions of steady recharge within groundwater models.Vadose Zone J. 13, 15, http://dx.doi.org/10.2136/vzj2013.10.0184. The code can be obtained at http://az.water.usgs.gov/software/damp.html
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To assess the current topography of the tidal marshes we conducted survey-grade elevation surveys at all sites between 2009 and 2013 using a Leica RX1200 Real Time Kinematic (RTK)Global Positioning System (GPS) rover (±1 cm horizontal, ±2 cm vertical accuracy; Leica Geosystems Inc., Norcross, GA; Figure 4). At sites with RTK network coverage (San Pablo, Petaluma, Pt. Mugu, and Newport), rover positions were received in real time from the Leica Smartnet system via a CDMA modem (www.lecia-geosystems.com). At sites without network coverage (Humboldt, Bolinas, Morro and Tijuana), rover positions were received in real time from a Leica GS10 antenna base station via radio link. When using the base station, we adjusted...
Our objective was to quantitatively characterize the landscape of climate-relevant resource decisions in the southwestern United States. We worked with stakeholders to determine actual uses of climate-relevant information used in natural resource decisions. We used content analysis of federal register records of decisions and stakeholder consultative groups to develop a survey of decision makers querying the use of climate information in decisions. We sought to create a classification of decisions attributes, information needs, and decision processes that rely on climate science. We sought to engage stakeholder consultative groups to define mechanisms for best filtering, delivering and interpreting what has become...
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Drought and wildfire pose enormous threats to the integrity of natural resources that land managers are charged with protecting. Recent observations and modeling forecasts indicate that these stressors will likely produce catastrophic ecosystem transformations, or abrupt changes in the condition of plants, wildlife, and their habitats, in regions across the country in coming decades. In this project, researchers will bring together land managers who have experienced various degrees of ecosystem transformation (from not yet experiencing any changes to seeing large changes across the lands they manage) to share their perspectives on how to mitigate large-scale changes in land condition. The team will conduct surveys...
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The distribution and abundance of cheatgrass, an invasive annual grass native to Eurasia, has increased substantially across the Intermountain West, including the Great Basin. Cheatgrass is highly flammable, and as it has expanded, the extent and frequency of fire in the Great Basin has increased by as much as 200%. These changes in fire regimes are associated with loss of the native sagebrush, grasses, and herbaceous flowering plants that provide habitat for many native animals, including Greater Sage-Grouse. Changes in vegetation and fire management have been suggested with the intent of conserving Greater Sage-Grouse. However, the potential responses of other sensitive-status birds to these changes in management...
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The 2017 fire season in California was highly unusual with its late seasonal timing, the areal extent it burned, and its devastation to communities. These fires were associated with extreme winds and were potentially also influenced by unusually dry conditions during several years leading up to the 2017 events. This fire season brought additional attention and emphasized the vital need for managers in the western U.S. to have access to scientific information on when and where to expect dangerous fire events. Understanding the multiple factors that cause extreme wildfire events is critical to short and long-term forecasting and planning. Seasonal climate measures such as temperature and precipitation are commonly...
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Fire has always been a part of life in southern California. Climate change and current fire management practices have led to catastrophic losses and impacts to human health, infrastructure and ecosystems, as seen, for example, in the 2018 Montecito debris flow. Indigenous wisdom instructs that rather than suppressing fire, we should seek to be in good relationship with fire. This project centers the voices of Chumash people by revitalizing their good relationship with fire in Chumash homelands. This revitalization comes at a critical time for both fire management and revitalization of Indigenous cultural burning practices in the southwest. The project will enable the recovery and documenting of Chumash knowledge...
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Streamflow in the Colorado River is heavily influenced by high-elevation snowpack. Warming temperatures in spring can reduce snow-fed flows, with serious implications for the water supplies that support communities and wildlife. While it is already well-known that precipitation has a significant influence on river flow, recent observations suggest that temperature and the amount of water in soil may also influence streamflow. In the face of a changing climate, it is important that resource managers understand how factors such as changing temperatures and precipitation will affect this vital water source. To address this need, researchers are examining records of streamflow, temperature, soil moisture, and precipitation...
This project links climate, hydrological, and ecological changes over the next 30 years in a Great Basin watershed. In recent years, climate variability on annual and decadal time scales has been recognized as greater than commonly perceived with increasing impacts on ecosystems and available water resources. Changes in vegetation distribution, composition and productivity resulting from climate change affect plant water use, which in turn can alter stream flow, groundwater and eventually available water resources. To better understand these links, project researchers implemented two computer-based numeric models in the Cleve Creek watershed in the Schell Creek Range, east of Ely, Nevada. The application of the...
Native Americans in the Southwest United States are thought to be particularly vulnerable to climate change. Tribal resiliency to climate change can be affected by multiple climate-related threats and by tribal communities’ close reliance on natural resources for sustenance, economic development, and maintenance of cultural traditions. A scientifically rigorous assessment of such threats to Native Americans is a pressing need across southwestern landscapes. This project examined factors affecting Native American tribes, including water rights for fish and wildlife, protection of wetlands, and enhancement and recovery of the Pyramid Lake, Nevada fishery, and protection of important fish species. This project aimed...
Abstract (from AMS100): Between water years 2012 and 2017, the Truckee–Carson river system in the western United States experienced both historic-low and record-high Sierra Nevada snowpack, anomalously warm temperatures, and winter and spring flooding. As part of an ongoing collaborative modeling research program in the river system, researchers conduct annual interviews with key local water managers to characterize local climate adaptation strategies and implementation barriers, and identify science information needs to prioritize ongoing research activities. This article presents new findings from a third wave of interviews conducted with the same water managers following the historic 2017 wet year. Comparison...
How quickly a lake fills after water is drawn for irrigation or drinking is easily measured, but that’s not true for underground water reserves, called aquifers. Because it takes place belowground, groundwater replenishment—or recharge—can’t be directly observed. Scientists must estimate it, often by using complex mathematical models. A new screening tool may now ease the task.
map background search result map search result map Examining the Influence of Temperature and Precipitation on Colorado River Water Resources: Reconstructing the Past to Understand the Future Relations Among Cheatgrass, Fire, Climate, and Sensitive-Status Birds across the Great Basin Tijuana: Tidal Marsh Digital Elevation Model Preventing Extreme Fire Events by Learning from History: The Effects of Wind, Temperature, and Drought Extremes on Fire Activity Learning From the Past and Planning for the Future: Experience-Driven Insight Into Managing for Ecosystem Transformations Induced by Drought and Wildfire Cycles of Renewal: Returning Good Fire to the Chumash Homelands Tijuana: Tidal Marsh Digital Elevation Model Cycles of Renewal: Returning Good Fire to the Chumash Homelands Examining the Influence of Temperature and Precipitation on Colorado River Water Resources: Reconstructing the Past to Understand the Future Preventing Extreme Fire Events by Learning from History: The Effects of Wind, Temperature, and Drought Extremes on Fire Activity Relations Among Cheatgrass, Fire, Climate, and Sensitive-Status Birds across the Great Basin Learning From the Past and Planning for the Future: Experience-Driven Insight Into Managing for Ecosystem Transformations Induced by Drought and Wildfire