Irrigation

Scientific American | January 17th, 1903

Irrigation in California

Scientific American | January 4th, 1890

Irrigation of Twelve Million Acres in the Valley of California

U.S. Geological Survey (USGS) | November 15th, 1920

Is climate change implicated in the 2013-2014 California drought? A hydrologic perspective

American Geophysical Union (AGU) | April 21st, 2015

California has experienced severe drought in 2012–2014 (which appears to be continuing into 2015), with especially low winter precipitation and mountain snowpack in wi

California has experienced severe drought in 2012–2014 (which appears to be continuing into 2015), with especially low winter precipitation and mountain snowpack in winter 2013–2014. However, the extent to which climate change is implicated in the drought, if at all, is not clear. By applying modeling and statistical approaches, we construct a historical record of California snowpack, runoff, and other hydrological variables of almost 100 years in length and use the reconstructed records to analyze climate trends in the Sierra Nevada and their impact on extreme drought events in the historic record. We confirm a general warming trend and associated decreasing trends in spring snowpack and runoff. We find that the warming may have slightly exacerbated some extreme events (including the 2013–2014 drought and the 1976–1977 drought of record), but the effect is modest; instead, these drought events are mainly the result of variability in precipitation.

Joshua Tree National Park: A History of Preserving the Desert

National Park Service (NPS) | March 16th, 2015

Klamath/San Joaquin/Sacramento Hydroclimatic Reconstructions from Tree Rings

California Department of Water Resources (DWR) | February 7th, 2014

This is a draft final report for Agreement Number 4600008850, “Klamath/San Joaquin/Sacramento Hydroclimatic Reconstructions”, signed October 13, 2010.  Work includes

This is a draft final report for Agreement Number 4600008850, “Klamath/San Joaquin/Sacramento Hydroclimatic Reconstructions”, signed October 13, 2010.  Work includes developing new and updated tree-ring chronologies, reconstructing specified streamflow and/or precipitation records in the Klamath, San Joaquin and Sacramento River Basins, and analyzing the time series properties of the reconstructions. These reconstructions allow assessment of hydrologic variability over centuries to millennia and give context for assessing recent drought events. Tasks on this project included field collections; laboratory work in sample preparation, dating and measurement; and statistical work in chronology development, reconstruction, and analysis of those reconstructions. The interpretation of the reconstructions includes five main components : 1) place instrumental-period flow statistics in a long-term context, 2) quantify droughts and wet periods, 3) identify cycles in wetness and dryness, 4) check consistency with other paleoclimatic data, and 5) assess reconstructed flow variations in the context of expected scenarios of climate. A total of 16 different hydroclimatic series – 11 flow records and 5 precipitation records, were reconstructed. This report summarizes the research project products and results. The Data and Methods section of this report describes the field collections and development of tree-ring chronologies, reconstruction modeling, and methods of analyzing reconstructions. The Results section focuses on the interpretation of selected key reconstructions for the Klamath, Sacramento, and San Joaquin basins. Annual time series of the 16 reconstructions are included as products in an appendix and in a digital spreadsheet.

Large closed-basin lakes sustainably supplied phosphate during the origins of life

American Association for the Advancement of Science (AAAS) | February 19th, 2025

The origin of life on Earth required a supply of phosphorus (P) for the synthesis of universal biomolecules. Closed lakes may have accumulated high P concentrations on ea

The origin of life on Earth required a supply of phosphorus (P) for the synthesis of universal biomolecules. Closed lakes may have accumulated high P concentrations on early Earth. However, it is not clear whether prebiotic P uptake in such settings would then have been sustainable. We show that large closed-basin lakes can combine high P concentrations at steady state with extremely high rates of biological productivity. Our case study is Mono Lake in California, which has close to 1 millimolar dissolved P at steady state despite extremely high rates of biological productivity, in contrast to smaller closed basins where life is scarce. Hence, large closed-basin lakes offer an environment where high rates of prebiotic P productivity can plausibly coexist with high steady-state P concentrations. Such lakes should have readily formed on the heavily cratered and volcanically active surface of early Earth.

Late Holocene Lacustrine Chronology and Archaeology of Ancient Lake Cahuilla, California

Quaternary Research (Elsevier) | May 1st, 1983

Freshwater lakes existed intermittently in the Salton Trough of southern California during the late Holocene. The lakes formed north of the subaerial Colorado River Delta

Freshwater lakes existed intermittently in the Salton Trough of southern California during the late Holocene. The lakes formed north of the subaerial Colorado River Delta whenever the Colorado River flowed west into the trough instead of south to the Gulf of California. Water filled the trough to a maximum altitude of 12 m. Stratigraphy, radiocarbon dates, and supplementary evidence document four lacustral intervals of Lake Cahuilla between A.D. 700 and 1580. Archaeological sites are associated with the 12-m shoreline and their occupation correlates with these lacustral intervals.

Late Pleistocene exploration and settlement of the Americas by modern humans

American Association for the Advancement of Science (AAAS) | June 12th, 2019

North and South America were the last continents to be explored and settled by modern humans at the end of the Pleistocene. Genetic data, derived from contemporary popul

North and South America were the last continents to be explored and settled by modern humans at the end of the Pleistocene. Genetic data, derived from contemporary populations and ancient individuals, show that the first Americans originated from Asia and after several population splits moved south of the continental ice sheets that covered Canada sometime between ~17.5 and ~14.6 thousand years (ka) ago. Archaeological evidence shows that geographically dispersed populations lived successfully, using biface, blade, and osseous technologies, in multiple places in North and South America between ~15.5 and ~14 ka ago. Regional archaeological complexes emerged by at least ~13 ka ago in North America and ~12.9 ka ago in South America. Current genetic and archaeological data do not support an earlier (pre–17.5 ka ago) occupation of the Americas.

Legal Aspects of Instream Water Uses in California: Background and Issues

California State Water Resources Control Board (SWRCB) | January 1st, 1978

This paper is part of a series of background and issue papers prepared by the staff of the Governor's Commission to Review California Water Rights Law. TABLE OF CONTEN

This paper is part of a series of background and issue papers prepared by the staff of the Governor's Commission to Review California Water Rights Law. TABLE OF CONTENTS I. Introduction II. The Nature of Property Rights III. State Water Resources Control Board Authority Related to Instream Uses IV.  Other Authority for the Protection and Enhancement of Instream Uses V. Methods of Protecting Instream Uses in Western States other than California VI.  Issues