Download or read book The Realism of Precipitation Extremes in High Resolution Gridded Datasets A Case Study Over California written by Matthew Grieco and published by . This book was released on 2018 with total page 57 pages. Available in PDF, EPUB and Kindle. Book excerpt: There is a growing need for high-resolution, spatially complete meteorological data. These data are utilized within weather, climate, ecological, and environmental research. With so many different gridded datasets available, it is unclear which is best for a given application. There are few comprehensive studies that have examined the strengths and weaknesses of gridded datasets, and they have mainly identified flaws or differences without understanding how these differences arise from the methodologies or suggesting ways to improve. Precipitation extremes are especially difficult to capture in gridded data. Here we assess precipitation extremes of five high-resolution gridded datasets over California to by comparing with daily station data and interpret the results in the context of each dataset's methodology. Multiple statistics of extreme precipitation were considered, reflecting intensity, frequency, and duration. Large differences are found both between the gridded datasets and relative to the station data. Maximum single day precipitation is underestimated in nearly all datasets, and precipitation frequency is severely overestimated in many cases. Datasets differ most notably in magnitude and precipitation occurrence in mountainous and coastal regions. The errors of these gridded datasets can vary significantly when compared to station data; one dataset within this study gives a 54% error for consecutive precipitation frequency. The results of this assessment are likely to be useful for users of gridded datasets looking to select a dataset appropriate for their research. They could also aid gridded dataset creators in improving existing products or building new ones.
Download or read book Geostatistics for Environmental Scientists written by Richard Webster and published by John Wiley & Sons. This book was released on 2007-10-22 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt: Geostatistics is essential for environmental scientists. Weather and climate vary from place to place, soil varies at every scale at which it is examined, and even man-made attributes – such as the distribution of pollution – vary. The techniques used in geostatistics are ideally suited to the needs of environmental scientists, who use them to make the best of sparse data for prediction, and top plan future surveys when resources are limited. Geostatistical technology has advanced much in the last few years and many of these developments are being incorporated into the practitioner’s repertoire. This second edition describes these techniques for environmental scientists. Topics such as stochastic simulation, sampling, data screening, spatial covariances, the variogram and its modeling, and spatial prediction by kriging are described in rich detail. At each stage the underlying theory is fully explained, and the rationale behind the choices given, allowing the reader to appreciate the assumptions and constraints involved.
Download or read book Extreme Value Analysis of Rainfall Events Over the Kennedy Space Center Complex written by Adam David Schnapp and published by . This book was released on 2014 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study used extreme-value theory to analyze a short period (15-year), high-density rainfall dataset from NASA Kennedy Space Center's observational network. The data was acquired through the Tropical Rainfall Measurement Mission archive website. The researcher employed the National Center for Atmospheric Research's Extremes statistical software package for the analysis of 24-hour rainfall at the locations of the 32 tipping-bucket gauges in the network. This type of analysis is highly sensitive to data that may have been misreported, invalid, or missing, therefore, additional quality control was required. The quality-controlled rainfall gauge data was subsequently gridded using a Barnes-style objective analysis with minimal smoothing, in order to estimate missing values while preserving maxima in the initial data. The high-resolution gridded rainfall data was used by the Extremes program to estimate a series of event return levels over the studied region. Analyses of the gridded data show that the 100-year events are around 315 mm and 433 mm for 24-hour and 72-hour durations, respectively. The wet-season analysis 100-year event estimation was around 426 mm and is similar to the yearly analysis, indicating that the majority of the annual extremes are from the wet-season events. The yearly and wet-season 100-year return levels appear to be realistic and consistent with previous literature and estimates from the longer period of record at Titusville; however, some results from the dry season analysis do not appear to be realistic, as they indicate the rainfall frequency distribution has an abnormally bounded tail shape. The dry-season 100-year-return-levels are likely greater than the 170 mm model consensus produced from the analysis of the gridded data. The better-behaved Titusville analysis suggests the dry-season 100-year return level is around 250 mm. Findings indicate large uncertainty associated with long-period estimates and high spatial variations in rainfall extremes across the Kennedy Space Center region.
Download or read book Spatial Statistics and Models written by G. L. Gaile and published by . This book was released on 2014-09-01 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Attribution of Extreme Weather Events in the Context of Climate Change written by National Academies of Sciences, Engineering, and Medicine and published by National Academies Press. This book was released on 2016-07-28 with total page 187 pages. Available in PDF, EPUB and Kindle. Book excerpt: As climate has warmed over recent years, a new pattern of more frequent and more intense weather events has unfolded across the globe. Climate models simulate such changes in extreme events, and some of the reasons for the changes are well understood. Warming increases the likelihood of extremely hot days and nights, favors increased atmospheric moisture that may result in more frequent heavy rainfall and snowfall, and leads to evaporation that can exacerbate droughts. Even with evidence of these broad trends, scientists cautioned in the past that individual weather events couldn't be attributed to climate change. Now, with advances in understanding the climate science behind extreme events and the science of extreme event attribution, such blanket statements may not be accurate. The relatively young science of extreme event attribution seeks to tease out the influence of human-cause climate change from other factors, such as natural sources of variability like El Niño, as contributors to individual extreme events. Event attribution can answer questions about how much climate change influenced the probability or intensity of a specific type of weather event. As event attribution capabilities improve, they could help inform choices about assessing and managing risk, and in guiding climate adaptation strategies. This report examines the current state of science of extreme weather attribution, and identifies ways to move the science forward to improve attribution capabilities.
Download or read book Assessment of Observational Uncertainty in Extreme Precipitation Over the Continental United States written by and published by . This book was released on 2018 with total page 66 pages. Available in PDF, EPUB and Kindle. Book excerpt: An extreme precipitation categorization scheme, developed to temporally and spatially visualize and track the multi-scale variability of extreme precipitation climatology, is introduced over the continental United States and used as the basis for an observational dataset intercomparison. The categorization scheme groups three-day precipitation totals exceeding 100 mm into five precipitation categories, or "P-Cats". To assess observational uncertainty across a range of precipitation measurement approaches, we compare in situ station data from the Global Historical Climatology Network-Daily (GHCN-D), satellite derived data from the Tropical Rainfall Measuring Mission (TRMM), gridded station data from the Parameter-elevation Regression on Independent Slopes Model (PRISM), global reanalysis from the Modern-Era Retrospective analysis for Research and Applications, version 2 (MERRA 2), and regional reanalysis from the North American Regional Reanalysis (NARR). While all datasets capture the principal spatial patterns of extreme precipitation climatology, results show considerable variability across the five-platform suite in P-Cat frequency, spatial extent, and magnitude. Higher resolution datasets, PRISM and TRMM, most closely resemble GHCN-D and capture a greater frequency of high-end totals relative to lower resolution products, NARR and MERRA-2. When all datasets are regridded to a common coarser grid, differences persist with datasets originally constructed at a high resolution maintaining the highest frequency and magnitude of P-Cats. Potential future applications of this scheme include tracking change in P-Cats over space and time, climate model evaluation, and assessment of model projected change.
Download or read book Spatial Interpolation for Climate Data written by Hartwig Dobesch and published by John Wiley & Sons. This book was released on 2013-03-01 with total page 338 pages. Available in PDF, EPUB and Kindle. Book excerpt: This title gives an authoritative look at the use of Geographical Information Systems (GIS) in climatology and meterology. GIS provides a range of strategies, from traditional methods, such as those for hydromet database analysis and management, to new developing methods. As such, this book will provide a useful reference tool in this important aspect of climatology and meterology study.
Download or read book Characteristics Origins and Recent Trends in Extreme Precipitation in the United States Including the Role of Atmospheric Rivers written by Maryam Asgari Lamjiri and published by . This book was released on 2019 with total page 124 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mitigating the impacts of extreme precipitation is particularly complicated in California, where more than 50% of precipitation typically falls in less than 120 hours annually, and where droughts and floods are extreme and frequent. Lack of reliable precipitation datasets with high temporal resolution has limited investigation of key (hourly) aspects of important storm characteristics that strongly modulate their impacts. Here, a newly-available quality-controlled long-term dense network of hourly precipitation observations in California is used with hourly to multi-day precipitation observations in the United States (U.S.) to study extremes across the U.S. and through time. Recent advances in atmospheric river (AR) monitoring and cataloging enabled not only the confirmation of ARs as primary sources of extreme precipitation along the U.S. west coast but also recognition of their lesser-known contributions to the eastern U.S. extremes. The coexistence of ARs and hurricanes, which has not yet been explored, is identified here to contribute substantially to eastern U.S. extreme precipitation. Storm duration, more so than hourly precipitation rates, is found to strongly modulate precipitation totals, especially in the western U.S. These findings emphasize the importance of improving forecasts of storm duration, which has high practical importance as longer storms are more likely to yield severe floods over large areas. A unique scaling method, the R-CAT scale, is applied to daily precipitation records to provide a basis for placing the extraordinary nature of several recent precipitation extremes in the context of historical storms. While confirming the increase in intensity and frequency of extreme storms in the eastern U.S., new results are found in the western U.S. identifying significant declines in annual maximum 3-day precipitation totals and frequency of R-CAT storms in this region. Results here also provide a deeper perspective on these overall trends, in that a significant shift towards more temporally uniform precipitation during the most extreme storms is identified in the eastern U.S. These findings provide improved scientific foundations for the development and implementation of effective hazard-mitigation, climate-adaptation, and water-management strategies in California and across the Nation.
Download or read book Statistical Downscaling and Bias Correction for Climate Research written by Douglas Maraun and published by Cambridge University Press. This book was released on 2018-01-18 with total page 365 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive and practical guide, providing technical background and user context for researchers, graduate students, practitioners and decision makers. This book presents the main approaches and describes their underlying assumptions, skill and limitations. Guidelines for the application of downscaling and the use of downscaled information in practice complete the volume.
Download or read book Climate Change Trend Analysis on Extreme Precipitation Over Shasta Dam Watershed Based on 159 year Long term Dynamic Downscaling written by Dylan Luke Cawthorne and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: California's interconnected water system is one of the most advanced water management systems in the world, and understanding of long-term trends in atmospheric and hydrologic behavior is increasingly being seen as vital to its future well-being. Knowledge of such trends is hampered by the lack of long period observation data and the uncertainty surrounding future projections of atmospheric models. This study examines historical precipitation trends over Shasta Dam Watershed (SDW), which lies upstream of one of the most important aspects of California's water system, Shasta Dam, using a dynamic downscaling methodology that can obtain reconstructed climate data at fine time-space scales. The methodology for reconstructing historical precipitation data over SDW started with the coarse-resolution historical 2 degree 20th Century Project (20CRv2c) reanalysis dataset from NOAA and CIRES. The Weather Research and Forecasting (WRF) model was then used to produce 159 years (1852- 2010) of long-term reconstructed hourly precipitation data at a 3 km spatial resolution over SDW. Trend analysis on this data indicated an increase in total precipitation over the study period as well as a growing intensity of extreme events such as 6, 12, 24, 48, and 72 hour storms. These results both inform long-term planning decisions regarding the future of Shasta Dam and California's water system and validate a methodology that can be used in data-sparse basins around the world.
Download or read book Cooperative Station Observations written by and published by . This book was released on 1989 with total page 104 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Turn Down the Heat written by A Report for the World Bank by the Potsdam Institute for Climate Impact Research and Analytics. and published by World Bank Publications. This book was released on 2013-06-19 with total page 253 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report focuses on the risks of climate change to development in Sub-Saharan Africa, South East Asia and South Asia. Building on the 2012 report, Turn Down the Heat: Why a 4°C Warmer World Must be Avoided, this new scientific analysis examines the likely impacts of present day, 2°C and 4°C warming on agricultural production, water resources, and coastal vulnerability. It finds many significant climate and development impacts are already being felt in some regions, and that as warming increases from present day (0.8°C) to 2°C and 4°C, multiple threats of increasing extreme heat waves, sea-level rise, more severe storms, droughts and floods are expected to have further severe negative implications for the poorest and most vulnerable. The report finds that agricultural yields will be affected across the three regions, with repercussions for food security, economic growth, and poverty reduction. In addition, urban areas have been identified as new clusters of vulnerability with urban dwellers, particularly the urban poor, facing significant vulnerability to climate change. In Sub-Saharan Africa, under 3°C global warming, savannas are projected to decrease from their current levels to approximately one-seventh of total land area and threaten pastoral livelihoods. Under 4°C warming, total hyper-arid and arid areas are projected to expand by 10 percent. In South East Asia, under 2°C warming, heat extremes that are virtually absent today would cover nearly 60-70 percent of total land area in northern-hemisphere summer, adversely impacting ecosystems. Under 4°C warming, rural populations would face mounting pressures from sea-level rise, increased tropical cyclone intensity, storm surges, saltwater intrusions, and loss of marine ecosystem services. In South Asia, the potential sudden onset of disturbances to the monsoon system and rising peak temperatures would put water and food resources at severe risk. Well before 2°C warming occurs, substantial reductions in the frequency of low snow years is projected to cause substantial reductions in dry season flow, threatening agriculture. Many of the worst climate impacts could still be avoided by holding warming below 2°C, but the window for action is closing rapidly. Urgent action is also needed to build resilience to a rapidly warming world that will pose significant risks to agriculture, water resources, coastal infrastructure, and human health.
Download or read book Assessment of Climate Change over the Indian Region written by R. Krishnan and published by Springer Nature. This book was released on 2020-06-12 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book discusses the impact of human-induced global climate change on the regional climate and monsoons of the Indian subcontinent, adjoining Indian Ocean and the Himalayas. It documents the regional climate change projections based on the climate models used in the IPCC Fifth Assessment Report (AR5) and climate change modeling studies using the IITM Earth System Model (ESM) and CORDEX South Asia datasets. The IPCC assessment reports, published every 6–7 years, constitute important reference materials for major policy decisions on climate change, adaptation, and mitigation. While the IPCC assessment reports largely provide a global perspective on climate change, the focus on regional climate change aspects is considerably limited. The effects of climate change over the Indian subcontinent involve complex physical processes on different space and time scales, especially given that the mean climate of this region is generally shaped by the Indian monsoon and the unique high-elevation geographical features such as the Himalayas, the Western Ghats, the Tibetan Plateau and the adjoining Indian Ocean, Arabian Sea, and Bay of Bengal. This book also presents policy relevant information based on robust scientific analysis and assessments of the observed and projected future climate change over the Indian region.
Download or read book The Ocean and Cryosphere in a Changing Climate written by Intergovernmental Panel on Climate Change (IPCC) and published by Cambridge University Press. This book was released on 2022-04-30 with total page 755 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Intergovernmental Panel on Climate Change (IPCC) is the leading international body for assessing the science related to climate change. It provides policymakers with regular assessments of the scientific basis of human-induced climate change, its impacts and future risks, and options for adaptation and mitigation. This IPCC Special Report on the Ocean and Cryosphere in a Changing Climate is the most comprehensive and up-to-date assessment of the observed and projected changes to the ocean and cryosphere and their associated impacts and risks, with a focus on resilience, risk management response options, and adaptation measures, considering both their potential and limitations. It brings together knowledge on physical and biogeochemical changes, the interplay with ecosystem changes, and the implications for human communities. It serves policymakers, decision makers, stakeholders, and all interested parties with unbiased, up-to-date, policy-relevant information. This title is also available as Open Access on Cambridge Core.
Download or read book Methods of Correction for Systematic Error in Point Precipitation Measurement for Operational Use written by Boris Sevruk and published by World Meteorological Organization. This book was released on 1982 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Second Assessment of Climate Change for the Baltic Sea Basin written by The BACC II Author Team and published by Springer. This book was released on 2015-04-03 with total page 515 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is an update of the first BACC assessment, published in 2008. It offers new and updated scientific findings in regional climate research for the Baltic Sea basin. These include climate changes since the last glaciation (approx. 12,000 years ago), changes in the recent past (the last 200 years), climate projections up until 2100 using state-of-the-art regional climate models and an assessment of climate-change impacts on terrestrial, freshwater and marine ecosystems. There are dedicated new chapters on sea-level rise, coastal erosion and impacts on urban areas. A new set of chapters deals with possible causes of regional climate change along with the global effects of increased greenhouse gas concentrations, namely atmospheric aerosols and land-cover change. The evidence collected and presented in this book shows that the regional climate has already started to change and this is expected to continue. Projections of potential future climates show that the region will probably become considerably warmer and wetter in some parts, but dryer in others. Terrestrial and aquatic ecosystems have already shown adjustments to increased temperatures and are expected to undergo further changes in the near future. The BACC II Author Team consists of 141 scientists from 12 countries, covering various disciplines related to climate research and related impacts. BACC II is a project of the Baltic Earth research network and contributes to the World Climate Research Programme.
Download or read book Empirical statistical Downscaling written by Rasmus E. Benestad and published by World Scientific. This book was released on 2008 with total page 228 pages. Available in PDF, EPUB and Kindle. Book excerpt: Empirical-statistical downscaling (ESD) is a method for estimating how local climatic variables are affected by large-scale climatic conditions. ESD has been applied to local climate/weather studies for years, but there are few ? if any ? textbooks on the subject. It is also anticipated that ESD will become more important and commonplace in the future, as anthropogenic global warming proceeds. Thus, a textbook on ESD will be important for next-generation climate scientists.