Preprints
Filtering by Subject: Climate
Paleoclimate Changes in the Pacific Northwest Over the Past 36,000 Years from Clumped Isotope Measurements and Isotope-Enabled Model Analysis
Published: 2021-04-07
Subjects: Climate, Geochemistry, Geology, Physical Sciences and Mathematics, Soil Science
Since the last glacial period, North America has experienced dramatic changes in regional climate, including the collapse of ice sheets and changes in effective precipitation. We use clumped isotopes and analysis of transient climate simulations to provide constraints on hydroclimate changes in the Pacific Northwest. The coldest soil temperatures (~10.5 ±1.°C to 14.9 ±1.2°C) occurred [...]
Orbital, the Box - An interactive educational tool for in-depth understanding of astronomical climate forcing.
Published: 2021-04-07
Subjects: Adult and Continuing Education, Astrophysics and Astronomy, Climate, Earth Sciences, Education, Educational Methods, Geology, Geophysics and Seismology, Higher Education, Instructional Media Design, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, The Sun and the Solar System
“Orbital, the Box” provides an interactive tool with graphical user interface (GUI) for stimulating active, visual learning for understanding of astronomical climate forcing. This cross-platform tool can be run locally on a personal computer using a standard web browser environment with no need for plugins, thus maximising accessibility for students and teachers alike. The tool facilitates in the [...]
Globally resolved surface temperatures since the Last Glacial Maximum
Published: 2021-03-31
Subjects: Climate, Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Climate changes across the last 24,000 years provide key insights into Earth system responses to external forcing. Climate model simulations and proxy data have independently allowed for study of this crucial interval; however, they have at times yielded disparate conclusions. Here, we leverage both types of information using paleoclimate data assimilation to produce the first observationally [...]
Crisis at the Salton Sea: The Vital Role of Science
Published: 2021-03-04
Subjects: Atmospheric Sciences, Biogeochemistry, Chemistry, Climate, Earth Sciences, Environmental Chemistry, Environmental Public Health, Environmental Sciences, Environmental Studies, Geochemistry, Geology, Geomorphology, Hydrology, Medicine and Health Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics, Public Health, Social and Behavioral Sciences
The Salton Sea—a hypersaline, terminal lake in southern California—is in crisis. A combination of mismanagement and competition among federal, state and local agencies has hindered efforts to address declining lake levels and unstable water chemistry. This delay has heightened the public health threat to regional communities as retreating shorelines expose dry lakebed— a source of potentially [...]
An uncertainty-focused database approach to extract spatiotemporal trends from qualitative and discontinuous lake-status histories
Published: 2021-03-01
Subjects: Climate, Earth Sciences, Geology, Geomorphology, Hydrology, Longitudinal Data Analysis and Time Series, Other Earth Sciences, Sedimentology, Statistical Methodology, Stratigraphy
Changes in lake status are often interpreted as palaeoclimate indicators due to their dependence on precipitation and evaporation. The Global Lake Status Database (GLSDB) has since long provided a standardised synopsis of qualitative lake status over the last 30,000 14C years. Potential sources of uncertainty however are not recorded in the GLSDB. Here we present an updated and improved [...]
Seasonal Rainfall Forecasts for the Yangtze River Basin in the Extreme Summer of 2020
Published: 2021-02-27
Subjects: Atmospheric Sciences, Climate, Meteorology
Seasonal forecasts for Yangtze River basin rainfall in June, May–June–July (MJJ) and June–July–August (JJA) 2020 are presented, following successful forecasts in previous years. The 3-month forecasts are based on dynamical predictions of an East Asian Summer Monsoon (EASM) index, which is transformed into regional-mean rainfall through linear regression. The June rainfall forecasts for the [...]
Shallow or deep? A reinterpretation of the Rifian Corridor’s unique sandy contourites
Published: 2021-02-25
Subjects: Climate, Earth Sciences, Geology, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Paleontology, Sedimentology, Stratigraphy
This study proposes that sandstone layers exposed in the Fez-Meknes region of Northern Morocco (Ben Allou (Sidi Chaded) and El Adergha localities), have been misinterpreted as unique examples of geostrophically-driven, deep marine (150 - 400 m water depth) sandy contourites. Instead, our independent paleontological, sedimentological, and stratigraphic analyses show that these sandstones represent [...]
The 3D Structure of Northern Hemisphere Blocking Events: Climatology, Role of Moisture, and Response to Climate Change
Published: 2021-02-16
Subjects: Atmospheric Sciences, Climate
We present a comprehensive composite analysis of the 3D structure of blocks and its response to future climate change over North Pacific, North Atlantic, and Russia in summers and winters. Using reanalysis and two large-ensemble datasets from CESM1 and GFDL-CM3, we investigate the following: The climatology of 3D structure, physical processes governing the temperature anomaly associated with [...]
Reduced High-Latitude Land Seasonality in Climates with Very High Carbon Dioxide
Published: 2021-02-10
Subjects: Atmospheric Sciences, Climate, Oceanography and Atmospheric Sciences and Meteorology
Observations of warm past climates and projections of future climate change show that the Arctic warms more than the global mean, particularly during winter months. Past warm climates such as the early Eocene had above-freezing Arctic continental temperatures year-round. In this paper, we show that a reduced Arctic land seasonality with increased greenhouse gases is a robust consequence of the [...]
Waste Incinerators Undermine Clean Energy Goals
Published: 2021-02-03
Subjects: Climate, Oil, Gas, and Energy
A national clean energy standard, modeled upon existing state-level Renewable Portfolio Standards, has been proposed to decarbonize the U.S. electric grid. Most such state policies include municipal solid waste incineration as a form of “renewable” energy, despite incineration’s prominent role in perpetuating environmental injustice. This study finds that incinerators emit more greenhouse gas [...]
Dynamical attribution of North Atlantic interdecadal predictability to oceanic and atmospheric turbulence under realistic and optimal stochastic forcing
Published: 2021-02-01
Subjects: Climate, Environmental Sciences, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Unpredictable variations in the ocean originate from both external atmospheric forcing and chaotic processes internal to the ocean itself, and are a crucial sink of predictability on interdecadal timescales. In a global ocean model, we present i.) an optimisation framework to compute the most efficient noise patterns to generate uncertainty and ii.) a uniquely inexpensive, dynamical method for [...]
The active and passive roles of the ocean in generating basin-scale heat content variability
Published: 2021-01-28
Subjects: Climate, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The role of ocean circulation in transforming surface forcing into interannual-to-multidecadal oceanic variability is an area of ongoing debate. Here, a novel method, establishing exact causal links, is used to quantitatively determine the role of ocean active and passive processes in transforming stochastic surface forcing into heat content variability. To this end, we use a global ocean model [...]
Data Reference Syntax (DRS) for bias-adjusted C3S-CMIP5 simulations
Published: 2021-01-27
Subjects: Climate
This document specifies the Data Reference Syntax (DRS) elements for managing bias-adjusted C3S-CMIP5 simulation data. The document includes file naming conventions and metadata as NetCDF attributes. The DRS elements are allowed to either assume values defined by Controlled Vocabularies (CV), or free text, or free text with build rules.
Further improvement of warming-equivalent emissions calculation
Published: 2021-01-21
Subjects: Climate
GWP* was recently proposed1 as a simple metric for calculating warming-equivalent emissions by equating a change in the rate of emission of a short-lived climate pollutant (SLCP) to a pulse emission of carbon-dioxide. Other metrics aiming to account for the time-dependent impact of SLCP emissions, such as CGWP, have also been proposed2. In 2019 an improvement to GWP* was proposed by Cain et al3, [...]
The influence of orbital parameters on the North American Monsoon system during the Last Interglacial Period
Published: 2020-12-17
Subjects: Atmospheric Sciences, Climate, Earth Sciences, Environmental Sciences, Hydrology, Oceanography and Atmospheric Sciences and Meteorology
The response of summer precipitation in the western U.S. to climate variability remains a subject of uncertainty. For example, paleoclimate records indicate the North American monsoon (NAM) was stronger and spatially more extensive during the Holocene, whereas recent modeling suggests a weakened NAM response to increasing temperatures. These illustrate diverging pictures of the NAM response to [...]