Climatology and changes in internal intensity distributions of global precipitation systems over 2001-2020 based on IMERG

Journal of Hydrology (Elsevier) | March 11th, 2023

The internal intensity distributions of precipitation systems are closely related to precipitation dynamics. Understanding its climatology and changing characteristics is

The internal intensity distributions of precipitation systems are closely related to precipitation dynamics. Understanding its climatology and changing characteristics is important for comprehending climate change, enhancing atmospheric model, and obtaining accurate hydrologic responses. However, due to the various limitations of precipitation observations, the internal intensity distributions of global precipitation systems have not been thoroughly investigated. This study uses the Integrated Multi-satellitE Retrievals for Global Precipitation Measurement (IMERG) data during 2001-2020 to investigate the internal intensity distributions of global precipitation systems, by analyzing the climatology and changes in the radial intensity distributions and the core-region intensity of precipitation systems. The results indicate that precipitation systems with larger spatial sizes tend to have higher intensity. Small- and medium-size precipitation systems exhibit the most obvious changes in the inner regions of precipitation systems, with higher intensity during 2001-2010 than 2011-2020. The large-size precipitation systems have slightly higher intensity at each radius of the systems during 2011-2020. Upon further investigation of the core-region intensity of precipitation systems, the small- and medium-size precipitation systems both exhibit significant decreases during 2001-2020 with trends at -1.13 and -2 mm/h per century, respectively. The large-size precipitation systems exhibit nonsignificant increasing trends during 2001-2020. The results also show regional differences, with decreased core-region intensity over most tropical regions and increased core-region intensity over most subtropical regions. This study provides an alternative perspective on the climatology and changing features of precipitation from the system view, and the results revealed could have significant implications on global climate change.

Closing Loopholes in Water Rights Systems to Save Water: The Colorado River Basin

American Geophysical Union (AGU) | August 26th, 2024

Co-producing actionable science for water utilities

Climate Services (Elsevier) | July 7th, 2016

This article explores the efforts of four water utilities to co-produce actionable science by forging partnerships with scientific institutions to explore integrating cl

This article explores the efforts of four water utilities to co-produce actionable science by forging partnerships with scientific institutions to explore integrating climate considerations into their specific management context. The experiences of these four utilities and their scientific partners, as part of the Piloting Utility Modeling Applications project of the Water Utility Climate Alliance, provide a wealth of empirical evidence to illustrate some of the core concepts formulated to explain how to produce usable information and how to link research to decision making. Through these four case studies of co-production, we identify three findings that bridge principles and practice: each utility engaged in contextualizing research; in building and leveraging knowledge networks; and in embracing an entrepreneurial approach to their research agenda. In several instances, unanticipated but innovative assessment techniques were developed by science partners in collaboration with water utilities to fit the utility’s specific needs. The paper concludes by discussing some of the hard realities of co-production illustrated by these cases that should be kept in mind by people contemplating similar projects.

Coachella Valley Water District Engineer's Report on Water Supply and Replenishment Assessment for the East Whitewater River Subbasin Area of Benefit

Coachella Valley Water District (CVWD) | April 15th, 2015

Coachella Valley Water District (CVWD) and Desert Water Agency (DWA) have been importing Colorado River water exchanged for State Water Project (SWP) water alloca

Coachella Valley Water District (CVWD) and Desert Water Agency (DWA) have been importing Colorado River water exchanged for State Water Project (SWP) water allocations to replenish the groundwater within the Coachella Valley Groundwater Basin since 1973. Groundwater replenishment within the East Whitewater River Subbasin began in 1997 through a pilot program at the Thomas E. Levy Groundwater Replenishment Facility (TEL Replenishment Facility). In 2004, the Martinez Canyon pilot project was brought online. If groundwater replenishment with imported water is eliminated, groundwater overdraft will result. Increased overdraft results in declining water levels, increased pump lifts, and increased energy consumption to pump groundwater for irrigation and domestic use. Extreme overdraft has the potential to cause ground surface subsidence and to impact water quality and groundwater storage volume.

Coagulant and Sorbent Efficacy in Removing Mercury from Surface Waters in the Cache Creek Watershed, California

U.S. Geological Survey (USGS) | February 25th, 2019

Cache Creek drains part of northern California’s Coast Ranges and is an important source of mercury (Hg) to the Sacramento–San Joaquin Delta. Cache Creek is c

Cache Creek drains part of northern California’s Coast Ranges and is an important source of mercury (Hg) to the Sacramento–San Joaquin Delta. Cache Creek is contaminated with Hg from several sources, including historical Hg and gold mines, native Hg in the soils, and active mineral springs. In laboratory experiments in a study conducted by the U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency, the use of coagulants and sorbents to immobilize Hg in water samples from high- concentration sources in the Cache Creek watershed was investigated. Three sites were selected for the collection of surface-water samples containing high and low concentrations of particulate-associated Hg. The high-particulate Hg samples were collected from Cache Creek Settling Basin duringstormflow conditions. The low-particulate Hg samples werecollected from two geochemically contrasting sites duringbase-flow conditions (downstream from a geothermal springand at the emergence point of a connate-water spring). Three coagulants were chosen for laboratory testing with the high-particulate sample— (1) ChitoVanTM HV 1.5 percent (shell based), (2) FerralyteTM 8131 (ferric sulfate based), and (3) UltrionTM 8186 (aluminum based). Each coagulant was tested at various dose amounts to determine the optimum dose rate for the high-particulate sample. The low-particulate source samples were passed through three sorbents— (1) chitosan flakes, (2) coconut shell-based activated carbon,and (3) coal-based activated carbon. In-line columns were packed with each material, and the untreated sample waspassed through each column at three different flow rates (0.1,0.5, and 1.0 liter per minute, L/min). For dose rates used in this study, ChitoVanTM reduced turbidity of the particulate sample by 85–91 percent, FerralyteTM reduced turbidity by 54–93 percent, and UltrionTMreduced turbidity by greater than 90 percent. At the lowest dose rate, ChitoVanTM achieved a 59- to 61-percent reduction in whole-water methylmercury (MeHg) concentrations and a 71- to 75-percent decrease in whole-water total mercury  (THg) concentrations. FerralyteTM achieved a 37- to 48-percent decrease in whole-water MeHg concentrations and a 37- to 48-percent reduction in whole-water THg concentrations. UltrionTM achieved a greater than 90-percent decrease in whole-water MeHg and THg concentrations. Mercury removal from the low-particulate samples was less efficient for the sorbent materials compared to the coagulants; less than 30 percent of THg was removed from any 500-milliliter aliquot using sorbent materials. The coal-based sorbent was the most versatile of the sorbents, removing THg to a similar extent from both low-particulatesource waters. The chitosan sorbent was the most effective atremoving THg from the low-particulate stream sample, but less effective for the low-particulate connate-spring sample. The Hg removal efficiency of the coconut sorbent decreasedquickly compared to the other two sorbents, indicating that sorption may be limited by the short contact times evaluated in this study.

Coastal flooding - potential projections: 2000–2100

California Energy Commission (CEC) | July 31st, 2012

The change in flooding potential along the California coast over the twenty?first century was estimated from both ocean wave and sea level rise projections produced from

The change in flooding potential along the California coast over the twenty?first century was estimated from both ocean wave and sea level rise projections produced from global climate model data. Changes in flooding potential were inferred from changes in wave runup (the vertical height reached by wave?driven water levels), which depends on the instantaneous sea level (or still water level), beach slope, and wave height and wave period. The still water level is the superposition of regional (or relative) mean sea level, the tide, and non?tide sea level fluctuations. Non?tide sea level fluctuations include both the steric response associated with El Niño–related variability that can persist up to a year or more, and local storm–forced variability (storm surge). The potential for greatest coastal flooding occurs when extremes in waves and still water level occur nearly simultaneously. Wave activity provides the primary driving force for coastal flooding. Wave model significant wave height (Hs) and non?tide sea level projections were generated for a seven global climate model simulations. Comparison of the Hs and nontide projections with wave model hindcast Hs and observed non?tide fluctuations suggest that the characteristics and incidence of extreme Hs and non?tide fluctuations will not increase appreciably over the twenty?first century. Thus, because astronomical tide?forcing will not increase, increases in relative mean sea level will largely determine the potential for increased ocean?driven flooding along the California coast. If relative mean sea level along the California coast reaches global mean sea level rise projections associated with climate change, extreme flooding events expected to occur once in about 100 years under stationary relative mean sea levels will occur annually.

Coastal hardening and what it means for the world’s sandy beaches

Publisher not available | December 5th, 2024

Coastal Plain of Orange County, Basin 8-001 Alternative to a Groundwater Sustainability Plan

Orange County Water District (OCWD) | January 1st, 2017

Coastal vulnerability across the Pacific dominated by El Niño/Southern Oscillation

Nature Portfolio (Springer Nature) | September 21st, 2015

To predict future coastal hazards, it is important to quantify any links between climate drivers and spatial patterns of coastal change. However, most studies of future c

To predict future coastal hazards, it is important to quantify any links between climate drivers and spatial patterns of coastal change. However, most studies of future coastal vulnerability do not account for the dynamic components of coastal water levels during storms, notably wave-driven processes, storm surges and seasonal water level anomalies, although these components can add metres to water levels during extreme events. Here we synthesize multi-decadal, co-located data assimilated between 1979 and 2012 that describe wave climate, local water levels and coastal change for 48 beaches throughout the Pacific Ocean basin. We find that observed coastal erosion across the Pacific varies most closely with El Niño/Southern Oscillation, with a smaller influence from the Southern Annular Mode and the Pacific North American pattern. In the northern and southern Pacific Ocean, regional wave and water level anomalies are significantly correlated to a suite of climate indices, particularly during boreal winter; conditions in the northeast Pacific Ocean are often opposite to those in the western and southern Pacific. We conclude that, if projections for an increasing frequency of extreme El Niño and La Niña events over the twenty-first century are confirmed, then populated regions on opposite sides of the Pacific Ocean basin could be alternately exposed to extreme coastal erosion and flooding, independent of sea-level rise.

Coastal wetland deposition of cathode metals from the world’s largest lithium-ion battery fire

Nature Portfolio (Springer Nature) | November 26th, 2025