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Record-Setting Ocean Warmth Continued in 2019

Advances in Atmospheric Sciences (Springer) | February 1st, 2020

Summary

Human-emitted greenhouse gases (GHGs) have resulted in a long-term and unequivocal warming of the planet (IPCC, 2019). More than 90% of the excess heat is stored within

Human-emitted greenhouse gases (GHGs) have resulted in a long-term and unequivocal warming of the planet (IPCC, 2019). More than 90% of the excess heat is stored within the world’s oceans, where it accumulates and causes increases in ocean temperature (Rhein et al., 2013; Abram et al., 2019). Because the oceans are the main repository of the Earth’s energy imbalance, measuring ocean heat content (OHC) is one of the best ways to quantify the rate of global warming (Trenberth et al., 2016; Von Schuckmann et al., 2016; Cheng et al., 2018). Following reports released in the previous two years (Cheng and Zhu, 2018; Cheng et al., 2019c), this article presents new OHC data for the year 2019. These data reveal that the world’s oceans (especially the upper 2000 m) in 2019 were the warmest in recorded human history. Specifically, the ocean heat anomaly (0−2000 m) in 2019 was 228 Zetta Joules (ZJ, 1 ZJ=1021 Joules) above the 1981−2010 average and 25 ZJ above 2018 (Table 1). The OHC values (for the upper 2000 m) were obtained from the Institute of Atmospheric Physics (IAP) ocean analysis (see “Data and methods” section, below), which uses a relatively new method to treat data sparseness and updates in the instruments that have been used to measure ocean temperature (Cheng et al., 2017). The evolution of OHC (Fig. 1) shows that the upper 2000 m OHC in 2019 was 228 ± 9 ZJ above the 1981–2010 average. The record-setting ocean warmth is also found in National Oceanic and Atmospheric Administration/National Center for Environmental Information (NOAA/NCEI) data, showing 217± 4 ZJ in 2019 above the 1981−2010 average (21 ZJ above 2018) (Table 1) (updated from Levitus et al. 2012). With these newly available IAP data, a ranking of the warmest years since the 1950s is now possible (Table 1). The past five years are the top five warmest years in the ocean historically with modern instruments, and the past ten years are also the top ten years on record. The same ranking also applies to NOAA/NCEI data (Table 1).

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Recovery plan for Central Valley winter-run chinook salmon, spring-run chinook salmon, and steelhead

National Marine Fisheries Service (NMFS) | July 7th, 2014

Summary

Recovery is the process by which listed species and their ecosystems are restored and their future is safeguarded to the point that protections under the Endangered Speci

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Recovery Plan for Sacramento-San Joaquin Delta native fishes

U.S. Fish and Wildlife Service (FWS) | November 26th, 1996

Summary

Eight fish species are included in the Sacramento-San Joaquin Delta Native Fishes Recovery Plan. The delta smelt is listed as a threatened species. The Sacramento splitta

Eight fish species are included in the Sacramento-San Joaquin Delta Native Fishes Recovery Plan. The delta smelt is listed as a threatened species. The Sacramento splittail (splittail) was proposed as a threatened species on January 6, 1994. This recovery plan will recommend restoration criteria for the splittail that would be appropriate recovery criteria should the species be listed. Longfin smelt, green sturgeon, spring-run, late fall-run, and San Joaquin fall-run chinook salmon are species of concern for which restoration criteria are recommended. Information is also included on Sacramento perch, a species believed to be extirpated from the Delta at this time. Habitat Requirements and Limiting Factors: The eight species included in this recovery plan depend on the Sacramento-San Joaquin Delta for a significant segment of their life history. Threats to the Delta ecosystem and these species include loss of habitat due to increased freshwater exports resulting in increased salinity, loss of shallow-water habitat due to dredging, diking and filling, introduced aquatic species that have disrupted the food chain, and entrainment (movement offish by currents produced by diversions) in State, Federal and private water diversion. State and Federal water projects have also changed the pattern and timing of flows through the Delta. The salmon races are affected by sport and commercial harvest as well as by interactions with hatchery stocks. Recovery and Restoration Objective: Delisting of delta smelt. Restoration of splittail, longfin smelt, green sturgeon, spring-run, late fall-run, San Joaquin fall-run chinook salmon, and Sacramento perch. Recovery and Restoration Criteria: Recovery criteria are quantifiable and species specific and can be used to (1) monitor effectiveness of recovery actions, (2) determine when a species has recovered to a secure level (stabilized), and (3) determine when a species qualifies for delisting. In many cases, criteria are based on two independent measures: population abundance and geographic distribution. For each species a historic base period was established using available data to characterize abundance and distribution during a pre-decline period. The time period over which abundance and distribution criteria must be met was set at five generations. For five of the eight species there is an additional requirement of meeting the criteria through a minimum number of years of stressful environmental conditions. Action Needed: 1. Enhance and restore aquatic and wetland habitat in the Sacramento-San Joaquin River estuary. 2. Reduce effects of commercial and recreational harvest. 3. Reduce effects of introduced aquatic species on Delta native fishes. 4. Change and improve enforcement ofregulatory mechanisms. 5. Conduct monitoring and research on fish biology and management requirements. 6. Assess recovery management actions and re-assess prioritization of actions. 7. Increase public awareness of importance of Delta native fishes.

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Recovery Plan for Tidal Marsh Ecosystems of Northern and Central California

U.S. Fish and Wildlife Service (FWS) | September 23rd, 2013

Summary

The Recovery Plan for Tidal Marsh Ecosystems of Northern and Central California features five endangered species: two endangered animals, California clapper rail (Rallus

The Recovery Plan for Tidal Marsh Ecosystems of Northern and Central California features five endangered species: two endangered animals, California clapper rail (Rallus longirostris obsoletus) and salt marsh harvest mouse (Reithrodontomys raviventris) and three endangered plants, Cirsium hydrophilum var. hydrophilum (Suisun thistle), Chloropyron molle ssp. molle (soft bird’s-beak), and Suaeda californica (California sea-blite). The biology of these species is at the core of the recovery plan, but the goal of this effort is the comprehensive restoration and management of tidal marsh1 ecosystems. This recovery plan is an expansion and revision of The California Clapper Rail and Salt Marsh Harvest Mouse Recovery Plan (U.S. Fish and Wildlife Service 1984). The historic distribution of the California clapper rail encompasses major tidal marshes between Humboldt Bay and Morro Bay, defining the approximate geographic scope of this recovery plan. In addition to the California clapper rail and the salt marsh harvest mouse, the plan also covers three focal listed plant species that were listed as federally endangered in the 1990s and the northernmost population of an additional plant species. Two of the species, Cirsium hydrophilum var. hydrophilum and Chloropyron molle ssp. molle (this species’ former name is Cordylanthus mollis ssp. mollis which is how it appears on the List of Threatened and Endangered Species, but we use the currently accepted name here), are restricted to the northern reaches of the San Francisco Bay Estuary. The other endangered tidal marsh plant, Suaeda californica, historically occurred in both San Francisco Bay and Morro Bay but, except for three reintroductions to San Francisco Bay, is now restricted to Morro Bay. Another federally listed plant, Chloropyron maritimum ssp. maritimum (salt marsh bird’s-beak; formerly Cordylanthus maritimus ssp. maritimus), has its northern range limit in Morro Bay. Morro Bay was omitted from the Salt Marsh Bird’s-beak Recovery Plan (U.S. Fish and Wildlife Service 1985a) because the taxonomic interpretation at the time classified this population in another subspecies that is not federally listed. Current taxonomic interpretation considers the Morro Bay population as Chloropyron maritimum ssp. maritimum. It is included in this recovery plan due to its co-location with Suaeda californica in Morro Bay. Though recovery strategies and actions are provided for the Morro Bay population of C. maritimum ssp. maritimum, recovery criteria are not, therefore, the species should not be considered covered by the recovery portion of the document. In addition, this recovery plan addresses 11 species or subspecies of concern. These include the salt marsh wandering shrew (Sorex vagrans halicoetes), Suisun shrew (Sorex ornatus sinuosus), San Pablo vole (Microtus californicus sanpabloensis), California black rail (Laterallus jamaicensis coturniculus), three song sparrow subspecies of the San Francisco Bay Estuary (Alameda song sparrow [Melospiza melodia ssp. pusillula], Suisun song sparrow [M.m. maxillaris] and San Pablo song sparrow [M.m. samuelis]), saltmarsh common yellowthroat (Geothlypis trichas sinuosa), old man tiger beetle (Cicindela senilis senilis), Lathryrus jepsonii ssp. jepsonii (delta tule pea), and Spartina foliosa (Pacific cordgrass). These species occur in a variety of tidal marsh habitats where they are limited by the requirements of moisture, salinity, topography, soil types, and climatic conditions. Adjacent uplands and ecotone areas are also crucial habitats for many of these species. Primary threats to all the listed species include historical and current habitat loss and fragmentation due to urban development, agriculture, and diking related to duck hunting; altered hydrology and salinity; non-native invasive species; inadequate regulatory mechanisms; disturbance; contamination; risk of extinction due to small population size; and the most central threat, sea level rise due to climate change.

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Recycled Water Research Needs in California: Monitoring and Treatment Performance for Constituents of Emerging Concern

California State Water Resources Control Board (SWRCB) | April 4th, 2017

Summary

The California State Water Resources Control Board (State Water Board) held a workshop on October 27-28, 2015 in Costa Mesa focused on the state of the science, monitorin

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Redefining expectations for urban water supply systems to fight wildfires

Springer Nature | March 5th, 2025

Summary

When considering massive new costs for urban water systems to fight wildfires, we also need to look hard at the distribution of benefits from these investments, and desig

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Reduced Moisture Transport Linked to Drought Propagation Across North America

American Geophysical Union (AGU) | July 24th, 2019

Summary

Droughts reduce the availability of water, which affects communities and ecosystems worldwide. Recent studies have shown that droughts may travel up to thousands of kilom

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Reduced resilience as an early warning signal of forest mortality

Nature Portfolio (Springer Nature) | October 7th, 2019

Summary

Climate-induced forest mortality is being widely observed across the globe. Predicting forest mortality remains challenging because the physiological mechanisms c

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Reducing Methylmercury Accumulation in the Food Webs of San Francisco Bay and Its Local Watersheds

San Francisco Estuary Institute (SFEI) | April 8th, 2014

Summary

San Francisco Bay (California, USA) and its local watersheds present an interesting case study in estuarine mercury (Hg) contamination. This review focuses on the most pr

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Reduction of Nitrates in Groundwater – Agricultural Expert Panel Report

California State Water Resources Control Board (SWRCB) | September 9th, 2014

Summary

Recommendations to the State Water Resources Control Board pertaining to the Irrigated Lands Regulatory Program The Agricultural Expert Panel (Panel) was convened to a

Recommendations to the State Water Resources Control Board pertaining to the Irrigated Lands Regulatory Program The Agricultural Expert Panel (Panel) was convened to address thirteen questions posed by the State Water Resources Control Board (State Water Board). The questions were primarily technical in nature, and are abbreviated below. 1. How can risk to or vulnerability of groundwater best be determined in the context of a regulatory program such as the Irrigated Lands Regulatory Program (ILRP)? 2. Evaluate and develop recommendations for the current approaches taken to assessing risk to or vulnerability of groundwater. 3. How can risk to or vulnerability of surface water best be determined in the context of a regulatory program such as the ILRP? 4. Evaluate and develop recommendations for the current approaches taken to assessing risk to or vulnerability of surface water. 5. What management practices are expected to be implemented and under what circumstances for the control of nitrogen? 6. What management practices are recommended for consideration by growers when they are selecting practices to put in place for the control of nitrogen? 7. Evaluate and make recommendations regarding the usage of various nitrogen management and accounting practices. 8. Evaluate and make recommendations regarding the most effective methods for ensuring growers have the knowledge required for effectively implementing recommended management practices. 9. What measurements can be used to verify that the implementations of management practices for nitrogen are as effective as possible? 10. Evaluate and make recommendations regarding the usage of various verification measurements of nitrogen control. 11. Evaluate the relative merits, and make recommendations regarding the usage of, surface water measurement systems derived from either receiving water or a discharge monitoring approach to identify problem discharges. 12. Evaluate and make recommendations on how best to integrate the results of the Nitrogen Tracking and Reporting System Task Force with any above recommendation regarding management practices and verification measures. 13. Evaluate and make recommendations on the reporting requirements to report budgeting and recording of nitrogen application on a management block basis versus reporting aggregated numbers on a nitrate loading risk unit level.

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Page : 351

Record-Setting Ocean Warmth Continued in 2019

Recovery plan for Central Valley winter-run chinook salmon, spring-run chinook salmon, and steelhead

Recovery Plan for Sacramento-San Joaquin Delta native fishes

Recovery Plan for Tidal Marsh Ecosystems of Northern and Central California

Recycled Water Research Needs in California: Monitoring and Treatment Performance for Constituents of Emerging Concern

Redefining expectations for urban water supply systems to fight wildfires

Reduced Moisture Transport Linked to Drought Propagation Across North America

Reduced resilience as an early warning signal of forest mortality

Reducing Methylmercury Accumulation in the Food Webs of San Francisco Bay and Its Local Watersheds

Reduction of Nitrates in Groundwater – Agricultural Expert Panel Report

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