Preprints
Filtering by Subject: Climate
Coherent streamflow variability in Monsoon Asia over the past eight centuries---links to oceanic drivers
Published: 2019-11-13
Subjects: Climate, Earth Sciences, Hydrology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The Monsoon Asia region is home to ten of the world’s biggest rivers, supporting the lives of 1.7 billion people who rely on streamflow for water, energy, and food. Yet, a synoptic understanding of multi-centennial streamflow variability for this region is lacking. Here we produce the first large scale streamflow reconstruction over Monsoon Asia (63 stations in 16 countries), using a novel [...]
Gulf Stream and Kuroshio Current are synchronized
Published: 2019-11-05
Subjects: Atmospheric Sciences, Climate, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Observational records show that sea surface temperatures along the Gulf Stream and Kuroshio tend to synchronize at decadal time scales. This synchronization, which we refer to as the Boundary Current Synchronization (BCS), is reproduced in global climate models with high spatial resolution. Both in observations and model simulations, BCS is associated with meridional migrations of the atmospheric [...]
Skillful multiyear predictions of ocean acidification in the California Current System
Published: 2019-10-10
Subjects: Biogeochemistry, Climate, Earth Sciences, Oceanography, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The California Current System (CCS) sustains economically valuable fisheries and is particularly vulnerable to ocean acidification, due to the natural upwelling of corrosive waters that affect ecosystem function. Marine resource managers in the CCS could benefit from advanced knowledge of ocean acidity on multiyear timescales. We use a novel suite of retrospective forecasts with an initialized [...]
Non-stationary teleconnection between the Pacific Ocean and Arctic sea ice
Published: 2019-10-08
Subjects: Atmospheric Sciences, Climate, Oceanography and Atmospheric Sciences and Meteorology, Other Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Over the last 40 years observations show a teleconnection between summertime Pacific Ocean sea-surface temperatures and September Arctic sea-ice extent. However, the short satellite observation record has made it difficult to further examine this relationship. Here, we use 30 fully-coupled general circulation models (GCMs) participating in Phase 5 of the Coupled Model Inter-comparison Project to [...]
The North American hydrologic cycle through the last deglaciation
Published: 2019-10-01
Subjects: Climate, Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
While the climate evolution of North America during the last deglaciation has received considerable attention, few detailed model–data comparisons of the deglacial hydroclimate have been conducted at the continental scale. Here we use a transient climate simulation of the last deglaciation and a synthesis of hydroclimate proxies from across the continent to broadly assess the moisture budget and [...]
Holocene relative sea-level changes and glacial isostatic adjustment of the U.S. Atlantic coast
Published: 2019-09-30
Subjects: Climate, Earth Sciences, Environmental Sciences, Geomorphology, Glaciology, Oceanography and Atmospheric Sciences and Meteorology, Other Earth Sciences, Physical Sciences and Mathematics, Sedimentology, Stratigraphy, Tectonics and Structure
The first quality-controlled Holocene sea-level database for the U.S. Atlantic coast has been constructed from 686 sea-level indicators. The database documents a decreasing rate of relative sea-level (RSL) rise through time with no evidence of sea level being above present in the middle to late Holocene. The highest rates of RSL rise are found in the mid-Atlantic region. We employ the database to [...]
Skillful seasonal prediction of key carbon cycle components: NPP and fire risk
Published: 2019-09-19
Subjects: Climate, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Seasonal forecasts of global CO₂ concentrations rely on the well-documented relationship with the El Niño–Southern Oscillation (ENSO), combined with estimated anthropogenic emissions. Here, we investigate the skill of the GloSea5 seasonal forecasting system for two carbon cycle processes that underlie the global CO₂–ENSO relationship: the impact of meteorological conditions on CO₂ uptake by [...]
Solar signals in observation indeed implied enhanced predictability since 1977
Published: 2019-08-28
Subjects: Climate, Meteorology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
This is a Correspondence submitted to Nature GeoScience following the undermentioned paper: Gabriel Chiodo, Jessica Oehrlein, Lorenzo M. Polvani, John C. Fyfe & Anne K. Smith, Insignificant influence of 11-year solar cycle on the North Atlantic Oscillation, Nature Geoscience, volume 12, pages 94–99 (2019). It is a non-peer reviewed preprint.
Collapse of Eurasian ice sheets 14,600 years ago was a major source of global Meltwater Pulse 1a
Published: 2019-08-21
Subjects: Climate, Earth Sciences, Environmental Sciences, Geology, Glaciology, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Rapid sea-level rise caused by the collapse of large ice sheets is a global threat to human societies. In the last deglacial period, the rate of global sea-level rise peaked at more than 4 cm/yr during Meltwater Pulse 1a, which coincided with the abrupt Bølling warming event 14,650 yr ago. However, the sources of the meltwater have proven elusive, and the contribution from Eurasian ice sheets has [...]
Shifting velocity of temperature extremes under climate change
Published: 2019-08-19
Subjects: Climate, Environmental Indicators and Impact Assessment, Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Rapid changes in climatic conditions threaten both socioeconomic and ecological systems, as these might not be able to adapt or to migrate at the same pace as that of global warming. In particular, an increase of weather and climate extremes can lead to increased stress on human and natural systems, and a tendency for serious adverse effects. Relying on the EURO-CORDEX simulations, we compare the [...]
High-resolution terrestrial climate, bioclimate and vegetation for the last 120,000 years
Published: 2019-08-14
Subjects: Climate, Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Paleobiology, Physical Sciences and Mathematics
The variability of climate has profoundly impacted a wide range of macroecological processes in the Late Quaternary. Our understanding of these has greatly benefited from palaeoclimate simulations, however, high-quality reconstructions of ecologically relevant climatic variables have been limited to a few selected time periods, thus impeding continuous time analyses. Here, we present a 0.5° [...]
A century of reduced ENSO variability during the Medieval Climate Anomaly
Published: 2019-08-12
Subjects: Climate, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Climate model simulations of El Niño–Southern Oscillation (ENSO) behavior for the last millennium demonstrate interdecadal to centennial changes in ENSO variability that can arise purely from stochastic processes internal to the climate system. That said, the instrumental record of ENSO does not have the temporal coverage needed to capture the full range of natural ENSO variability observed in [...]
Bayesian calibration of the Mg/Ca paleothermometer in planktic foraminifera
Published: 2019-08-06
Subjects: Climate, Earth Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
The Mg/Ca ratio of planktic foraminifera is a widely-used proxy for sea-surface temperature, but is also sensitive to other environmental factors. Previous work has relied on correcting Mg/Ca for non-thermal influences. Here, we develop a set of Bayesian models for Mg/Ca in four major planktic groups -- Globigerinoides ruber (including both pink and white chromotypes), Trilobatus sacculifer, [...]
Assessing Climate Model Projections of Anthropogenic Warming Patterns
Published: 2019-07-16
Subjects: Climate, Earth Sciences, Environmental Sciences, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Projections of future anthropogenic climate change and their uncertainties are determined by analyzing large ensembles of numerical climate models. Since the late 1980s, transient climate models have projected a pronounced global warming, with relatively high warming in the Arctic and over land and low warming over the Southern Ocean. In general, confidence in climate model projections is based [...]
Reducing uncertainties in climate projections with emergent constraints: Concepts, Examples and Prospects
Published: 2019-06-28
Subjects: Atmospheric Sciences, Climate, Oceanography and Atmospheric Sciences and Meteorology, Physical Sciences and Mathematics
Models disagree on a significant number of responses to climate change, such as climate feedback, regional changes, or the strength of equilibrium climate sensitivity. Emergent constraints aim to reduce these uncertainties by finding links between the inter-model spread in an observable predictor and climate projections. In this paper, the concepts underlying this framework are recalled with an [...]