Global warming and 21st century drying - Lamont
... increases with warming, even at constant relative humidity (e.g., Anderson 1936). Actual evapotranspiration is expected to increase less than PET in areas where latent heat fluxes are, or will become, limited by moisture supply. Indeed, declines in global actual evapotranspiration have been document ...
... increases with warming, even at constant relative humidity (e.g., Anderson 1936). Actual evapotranspiration is expected to increase less than PET in areas where latent heat fluxes are, or will become, limited by moisture supply. Indeed, declines in global actual evapotranspiration have been document ...
Numerical Stabilization of Convection-Diffusion
... performance of finite element formulations for the advection-diffusion equation with production. While the GGLS method is nodally exact for one-dimensinal solutions, the GLS method is not. In the latter case, several choices of parameters are derived, which optimize the solutions according to certai ...
... performance of finite element formulations for the advection-diffusion equation with production. While the GGLS method is nodally exact for one-dimensinal solutions, the GLS method is not. In the latter case, several choices of parameters are derived, which optimize the solutions according to certai ...
www.ivt.ethz.ch
... • The actors involved are increasingly large Able to have a “big bang” approach, implies large investments • The level of competition on the market is increasing Higher investment risk ...
... • The actors involved are increasingly large Able to have a “big bang” approach, implies large investments • The level of competition on the market is increasing Higher investment risk ...
Future Climate, Hydrology, Vegetation, and Wildfire Projections for
... on physical, chemical, and biological processes that form the earth’s climate system. These models vary in their level of detail and assumptions, making output and future scenarios variable. Differences among ...
... on physical, chemical, and biological processes that form the earth’s climate system. These models vary in their level of detail and assumptions, making output and future scenarios variable. Differences among ...
How Does a Regional Climate Model Modify the Projected Climate
... climate simulations for 1950–2005 are driven by observed anthropogenic forcing. The climate projections are driven by projected anthropogenic forcing according to different Representative Concentration Pathways (RCPs). The global simulations are downscaled with REMO over the Coordinated Regional Cli ...
... climate simulations for 1950–2005 are driven by observed anthropogenic forcing. The climate projections are driven by projected anthropogenic forcing according to different Representative Concentration Pathways (RCPs). The global simulations are downscaled with REMO over the Coordinated Regional Cli ...
Mathematical Formalisms in Scientific Practice: From Denotation to
... capacity of mathematical models. Whether or not a model represents a physical system, or phenomenon, cannot be a question of whether or not it accurately mirrors every single detail; such a criterion would be far too strong, not only because it could hardly ever be met (except in the most simplistic ...
... capacity of mathematical models. Whether or not a model represents a physical system, or phenomenon, cannot be a question of whether or not it accurately mirrors every single detail; such a criterion would be far too strong, not only because it could hardly ever be met (except in the most simplistic ...
effects of changing climate on weather and human activities
... other heat-trapping gasses in the atmosphere. The climate is changing, and human activities are now part of the cause. But how does a climate change manifest itself in day-to-day weather? This book approaches the topic by explaining distinctions between weather and climate and how the rich natural v ...
... other heat-trapping gasses in the atmosphere. The climate is changing, and human activities are now part of the cause. But how does a climate change manifest itself in day-to-day weather? This book approaches the topic by explaining distinctions between weather and climate and how the rich natural v ...
Hydrological Climate Change Impact Assessment at Small and
... approach where climate model output data, usually precipitation and temperature from a Regional Climate Model (RCM), are extracted for the basin in question and then used to drive a hydrological model. It was early recognized that uncertainties in climate modelling had a strong influence on hydrolog ...
... approach where climate model output data, usually precipitation and temperature from a Regional Climate Model (RCM), are extracted for the basin in question and then used to drive a hydrological model. It was early recognized that uncertainties in climate modelling had a strong influence on hydrolog ...
Similar estimates of temperature impacts on global wheat
... data from 30 individual field sites deemed to represent two-thirds of wheat-producing areas worldwide8 . In this point-based approach estimates from sentinel sites were scaled up and extrapolated to cover geographical areas with similar conditions. In further contrast, statistical regressions based ...
... data from 30 individual field sites deemed to represent two-thirds of wheat-producing areas worldwide8 . In this point-based approach estimates from sentinel sites were scaled up and extrapolated to cover geographical areas with similar conditions. In further contrast, statistical regressions based ...
PDF
... growth, excessive precipitation events can dramatically reduce crop production (Rosenzweig et al., 2002). High temperatures reduce soil moisture, which negatively impacts crop yields, but these impacts may be offset by either precipitation or supplemental irrigation (Mitchell et al., 1990). To allow ...
... growth, excessive precipitation events can dramatically reduce crop production (Rosenzweig et al., 2002). High temperatures reduce soil moisture, which negatively impacts crop yields, but these impacts may be offset by either precipitation or supplemental irrigation (Mitchell et al., 1990). To allow ...
Guidelines for Use of Climate Scenarios Developed from Statistical
... Statistical downscaling involves developing quantitative relationships between large–scale atmospheric variables (predictors) and local surface variables (predictands). The most common form has the predictand as a function of the predictor(s), but other types of relationships have been used. For exa ...
... Statistical downscaling involves developing quantitative relationships between large–scale atmospheric variables (predictors) and local surface variables (predictands). The most common form has the predictand as a function of the predictor(s), but other types of relationships have been used. For exa ...
Predicting survival, reproduction and abundance of polar bears
... parameters due to climate change were not considered. However, our understanding of polar bear life history and ecology implies that such changes are likely. Quantitative predictions of population dynamics under environmental change must account for potential changes in reproduction and survival to ...
... parameters due to climate change were not considered. However, our understanding of polar bear life history and ecology implies that such changes are likely. Quantitative predictions of population dynamics under environmental change must account for potential changes in reproduction and survival to ...
Progress and Challenges In Biogeochemical Modeling Of The
... a combination of a set of differential equations, some algebraic equations, and a parameter list (Box 1). They have been used for several decades in an attempt to explain, analyze, and predict what we can only sparsely measure. With their ability to extend over spatial and temporal scales far beyond ...
... a combination of a set of differential equations, some algebraic equations, and a parameter list (Box 1). They have been used for several decades in an attempt to explain, analyze, and predict what we can only sparsely measure. With their ability to extend over spatial and temporal scales far beyond ...
Communicating the Impacts of Potential Future Climate Change on
... A novel methodology for determining future rainfall frequency is described in this report. Isohyetal maps illustrate how heavy precipitation may change in the future, but the results have a high level of uncertainty expressed as very wide confidence limits. Uncertainty in possible future conditions ...
... A novel methodology for determining future rainfall frequency is described in this report. Isohyetal maps illustrate how heavy precipitation may change in the future, but the results have a high level of uncertainty expressed as very wide confidence limits. Uncertainty in possible future conditions ...
Numerical weather prediction
Numerical weather prediction uses mathematical models of the atmosphere and oceans to predict the weather based on current weather conditions. Though first attempted in the 1920s, it was not until the advent of computer simulation in the 1950s that numerical weather predictions produced realistic results. A number of global and regional forecast models are run in different countries worldwide, using current weather observations relayed from radiosondes, weather satellites and other observing systems as inputs.Mathematical models based on the same physical principles can be used to generate either short-term weather forecasts or longer-term climate predictions; the latter are widely applied for understanding and projecting climate change. The improvements made to regional models have allowed for significant improvements in tropical cyclone track and air quality forecasts; however, atmospheric models perform poorly at handling processes that occur in a relatively constricted area, such as wildfires.Manipulating the vast datasets and performing the complex calculations necessary to modern numerical weather prediction requires some of the most powerful supercomputers in the world. Even with the increasing power of supercomputers, the forecast skill of numerical weather models extends to about only six days. Factors affecting the accuracy of numerical predictions include the density and quality of observations used as input to the forecasts, along with deficiencies in the numerical models themselves. Post-processing techniques such as model output statistics (MOS) have been developed to improve the handling of errors in numerical predictions.A more fundamental problem lies in the chaotic nature of the partial differential equations that govern the atmosphere. It is impossible to solve these equations exactly, and small errors grow with time (doubling about every five days). Present understanding is that this chaotic behavior limits accurate forecasts to about 14 days even with perfectly accurate input data and a flawless model. In addition, the partial differential equations used in the model need to be supplemented with parameterizations for solar radiation, moist processes (clouds and precipitation), heat exchange, soil, vegetation, surface water, and the effects of terrain. In an effort to quantify the large amount of inherent uncertainty remaining in numerical predictions, ensemble forecasts have been used since the 1990s to help gauge the confidence in the forecast, and to obtain useful results farther into the future than otherwise possible. This approach analyzes multiple forecasts created with an individual forecast model or multiple models.