The role of the Gulf of California (GoC) in the North American Monsoon (NAM) is investigated using a global climate model with 50 km horizontal atmospheric resolution and prescribed SSTs. Specifically, two 135 year simulations are compared to quantify the influence of the GoC on the NAM: in the first simulation a realistic representation of the…

A vertically resolved moist static energy (MSE) variance budget framework is used to diagnose processes associated with the development of tropical cyclones (TCs) in a general circulation model (GCM) under realistic boundary conditions. Previous studies have shown that interactions between radiation and MSE promotes TC development. Here we…

Global radiative feedbacks exhibit large dependence on the spatial structure of sea surface temperature (SST) changes, which is referred to as the “pattern effect”. A Green’s function (GF) approach has been demonstrated to be useful in identifying and understanding contributions of regional SST changes to global radiative feedbacks. Here, we…

This work uses reanalysis and NOAA Geophysical Fluid Dynamics Laboratory's Coupled Model Intercomparison Project 6 model, CM4, to investigate the colocation of heat extremes and atmospheric blocking in the current climate and an end of 21st century, extreme-emissions projection. In the present day, the colocation of heat events and blocking is…

Gender equity, providing for full participation of people of all genders in the oceanographic workforce, is an important goal for the continued success of the oceanographic enterprise. Here, we describe historical obstructions to gender equity; assess recent progress and the current status of gender equity in oceanography by examining…

Interpreting behaviors of low-level clouds (LLCs) in a climate model is often not straightforward. This is particularly so over polar oceans where frozen and unfrozen surfaces coexist, with horizontal winds streaming across them, shaping LLCs. To add clarity to this interpretation issue, we conduct budget analyses of LLCs using a global…

The poleward heat flux by atmospheric waves plays a pivotal role in maintaining the meridional temperature gradient. A recent study found that in the Northern Hemisphere the heat flux by transient eddies has been weakening, and the study attributed this weakening to the smaller equator-to-pole temperature gradient caused by Arctic warming…

Traditional general circulation models, or GCMs—that is, three-dimensional dynamical models with unresolved terms represented in equations with tunable parameters—have been a mainstay of climate research for several decades, and some of the pioneering studies have recently been recognized by a Nobel prize in Physics. Yet, there is considerable…

We propose an integrated dynamics-physics coupling framework for weather and climate-scale models. Each physical parameterization would be advanced on its natural time scale, revise the thermodynamics to include moist effects, and finally integrated into the relevant components of the dynamical core. We show results using a cloud microphysics…

For over two decades, satellite ocean color missions have revealed spatio-temporal variations in marine chlorophyll. Seasonal cycles and interannual changes of the physical environment drive the nutrient and chlorophyll variations. In order to identify contributions of seasonal and interannual components on chlorophyll, the present study…

In December 2020, giant tabular iceberg A68a (surface area 3900 km2) broke up in open ocean much deeper than its keel, indicating that the breakage was not immediately caused by collision with the seafloor. Giant icebergs with lengths exceeding 18.5 km account for most of the calved ice mass from the Antarctic Ice Sheet. Upon calving, they…

Numerical and observational evidence indicates that, in regions where mixed-layer instability is active, the surface geostrophic velocity is largely induced by surface buoyancy anomalies. Yet, in these regions, the observed surface kinetic energy spectrum is steeper than predicted by uniformly stratified surface quasigeostrophic theory. By…

The tropical intraseasonal variability in an idealized moist general circulation model (GCM) coupled to a slab ocean is investigated. The model has a simple moist convection scheme and realistic radiative transfer, but no parameterization of cloud processes. In a zonally symmetric aquaplanet state, variability is dominated by westward…

The destructive potential of a tropical cyclone (TC) is primarily determined by its intensity and outer size. Although TC intensification has been researched extensively, the growth rate of its outer size remains obscure. This prompts us to develop the concept of rapid growth of outer size (RG) of TCs. RG is defined as an increase of at least…

Intense convection (updrafts exceeding 10 m s−1) plays an essential role in severe weather and Earth's energy balance. Despite its importance, how the global pattern of intense convection changes in response to warmed climates remains unclear, as simulations from traditional climate models are too coarse to simulate intense convection…

We examine polarimetric rainfall estimates of extreme rainfall through intercomparisons of radar rainfall estimates with rainfall observations from a dense network of rain gauges in Kansas City. The setting provides unique capabilities for examining range dependence in polarimetric rainfall estimates due to the overlapping coverage of the…

CO2-forced surface warming in general circulation models (GCMs) is initially polar-amplified in the Arctic but not Antarctic—a largely hemispherically antisymmetric signal. Nevertheless, we show in CESM1 and eleven LongRunMIP GCMs that the hemispherically symmetric component of global-mean-normalized, zonal-mean warming (T∗sym) under 4×CO2…

Understanding the behavior of western boundary current systems is crucial for predictions of biogeochemical cycles, fisheries, and basin-scale climate modes over the midlatitude oceans. Studies indicate that anthropogenic climate change induces structural changes in the Kuroshio Extension (KE) system, including a northward migration of its…

Multidecadal variability of Atlantic Meridional Overturning Circulation (AMOC) has been reconstructed by various proxies, simulated in climate models, and linked to multidecadal Arctic salinity variability. Here we construct a simple conceptual model to understand the two-way interactions of the Arctic with multidecadal AMOC variability through…

Quantifying the response of atmospheric rivers (ARs) to radiative forcing is challenging due to uncertainties caused by internal climate variability, differences in shared socioeconomic pathways (SSPs), and methods used in AR detection algorithms. In addition, the requirement of medium-to-high model resolution and ensemble sizes to explicitly…

This paper examines the physical controls of extratropical humidity and clouds by isolating the effects of cloud physics factors in an idealized model. The Held–Suarez dynamical core is used with the addition of passive water vapor and cloud tracers, allowing cloud processes to be explored cleanly. Separate saturation adjustment and full cloud…

Tropical cyclone (TC) rainfall hazard assessment is subject to the bias in TC climatology estimation from climate simulations or synthetic downscaling. In this study, we investigate the uncertainty in TC rainfall hazard assessment induced by this bias using both rain gauge and radar observations and synthetic-storm-model-coupled TC rainfall…

We describe the third version of the Geophysical Fluid Dynamics Laboratory cloud microphysics scheme (GFDL MP v3) implemented in the System for High-resolution prediction on Earth-to-Local Domains (SHiELD). Compared to the GFDL MP v2, the GFDL MP v3 is entirely reorganized, optimized, and modularized into functions. The particle size…

Two-way multiple same-level and telescoping grid nesting capabilities are implemented in the Geophysical Fluid Dynamics Laboratory (GFDL)'s Finite-Volume Cubed-Sphere Dynamical Core (FV3). Simulations are performed within GFDL's System for High-resolution modeling for Earth-to-Local Domains (SHiELD) using global and regional multiple nest…

Marine heatwaves (MHWs), prolonged ocean temperature extremes, have been enhanced by global warming in recent decades. More intense and longer MHWs have increasingly negative impacts on marine organisms that threaten their resilience of marine ecosystems. In this study, we investigated global marine phytoplankton biomass (chlorophyll) estimated…

The discrete baroclinic modes of quasigeostrophic theory are incomplete and the incompleteness manifests as a loss of information in the projection process. The incompleteness of the baroclinic modes is related to the presence of two previously unnoticed stationary step-wave solutions of the Rossby wave problem with flat boundaries. These step…

Tropical anvil clouds are an important player in Earth’s climate and climate sensitivity, but simulations of anvil clouds are uncertain. Here we identify and investigate one source of uncertainty by demonstrating a marked increase of anvil cloud fraction with resolution in cloud-resolving simulations of radiative-convective equilibrium. This…

The El Niño-Southern Oscillation (ENSO) strongly influences phytoplankton in the tropical Pacific, with El Niño conditions suppressing productivity in the equatorial Pacific (EP) and placing nutritional stresses on marine ecosystems. The Geophysical Fluid Dynamics Laboratory's (GFDL) Earth System Model version 4.1 (ESM4.1) captures observed…

Intermittent transitions between turbulent and nonturbulent states are ubiquitous in the stable atmospheric surface layer (ASL). Data from two field experiments in Utqiaġvik, Alaska, and from direct numerical simulations are used to probe these state transitions so as to (i) identify statistical metrics for the detection of intermittency, (ii)…

The once-contiguous Ellesmere Ice Shelf, first reported in writing by European explorers in 1876, and now almost completely disintegrated, has rolling, wave-like surface topography, the origin of which we investigate using a viscous buckling instability analysis. We show that rolls can develop during a winter season (~ 100 d) if sea-ice…

The local climatic impacts of historical expansion of irrigation are substantial, but the distant impacts are poorly understood, and their governing mechanisms generally have not been rigorously analyzed. Our experiments with an earth-system model suggest that irrigation in the Middle East and South Asia may enhance rainfall in a large portion…

Laterally confined marine outlet glaciers exhibit a diverse range of behaviours. This study investigates time-evolving and steady configurations of such glaciers. Using simplified analytic models, it determines conditions for steady states, their stability and expressions for the rate of the calving-front migration for three widely used calving…

Large tabular icebergs account for the majority of ice mass calved from Antarctic ice shelves, but are omitted from climate models. Specifically, these models do not account for iceberg breakup and as a result, modeled large icebergs could drift to low latitudes. Here, we develop a physically based parameterization of iceberg breakup based on…

Ocean circulation models have systematic errors in large-scale horizontal density gradients due to estimating the grid-cell-mean density by applying the nonlinear seawater equation of state to the grid-cell-mean water properties. In frontal regions where unresolved subgrid-scale (SGS) fluctuations are significant, dynamically relevant errors in…

A negative shortwave cloud feedback associated with higher extratropical liquid water content in mixed-phase clouds is a common feature of global warming simulations, and multiple mechanisms have been hypothesized. A set of process-level experiments performed with an idealized global climate model (a dynamical core with passive water and cloud…

GCM-Filters is a python package that allows scientists to perform spatial filtering analysis
in an easy, flexible and efficient way. The package implements the filtering method based on
the discrete Laplacian operator that was introduced by Grooms et al. (2021). The filtering
algorithm is analogous to smoothing via diffusion; hence the…

The air quality impact of increased wildfires in a warming climate has often been overlooked in current model projections, owing to the lack of interactive fire emissions of gases and particles responding to climate change in Earth System Model (ESM) projection simulations. Here, we combine multiensemble projections of wildfires in three ESMs…

The Fires, Asian, and Stratospheric Transport–Las Vegas Ozone Study (FAST-LVOS) was conducted in May and June of 2017 to study the transport of ozone (O3) to Clark County, Nevada, a marginal non-attainment area in the southwestern United States (SWUS). This 6-week (20 May–30 June 2017) field campaign used lidar,…

Are the oceans turning into deserts? Rising temperature, increasing surface stratification, and decreasing vertical inputs of nutrients are expected to cause an expansion of warm, nutrient deplete ecosystems. Such an expansion is predicted to negatively affect a trio of key ocean biogeochemical features: phytoplankton biomass, primary…

Gas bubbles bursting at the sea surface produce drops, which contribute to marine aerosols. The contamination or enrichment of water by surface-active agents, of biological or anthropogenic origin, has long been recognized as affecting the bubble bursting processes and the spray composition. However, despite an improved understanding of the…

The current GFDL seasonal prediction system, the Seamless System for Prediction and EArth System Research (SPEAR), has shown skillful prediction of Arctic sea ice extent with atmosphere and ocean constrained by observations. In this study we present improvements in sub-seasonal and seasonal predictions of Arctic sea ice by directly assimilating…

Ocean variability is a dominant source of remote rainfall predictability, but in many cases the physical mechanisms driving this predictability are not fully understood. This study examines how ocean mesoscales (i.e., the Gulf Stream SST front) affect decadal southeast US (SEUS) rainfall, arguing that the local imprint of large-scale…

Bubbles bursting at the ocean surface are an important source of sea-spray aerosol. Indeed, a bubble bursting at the surface of a liquid produces a jet that then breaks up leading to several droplets. Here we simulate the bursting of a single bubble by numerical simulation of the axisymmetric two-phases air-water Navier-Stokes equations in the…

During El Niño events, a strong tropics-wide warming of the free troposphere is observed (of order 1 K at 300 hPa). This warming plays an important role for the teleconnection processes associated with El Niño but it remains unclear what initiates this warming. Since convective quasi-equilibrium only holds in regions of deep convection, the…

The continuing decline of the summertime sea ice cover has reduced the sea ice path that must be traversed to Arctic destinations and through the Arctic between the Atlantic and Pacific Oceans, stimulating interest in trans-Arctic Ocean routes. Seasonal prediction of the sea ice cover along these routes could support the increasing summertime…

Breaking waves modulate the transfer of energy, momentum, and mass between the ocean and atmosphere, controlling processes critical to the climate system, from gas exchange of carbon dioxide and oxygen to the generation of sea spray aerosols that can be transported in the atmosphere and serve as cloud condensation nuclei. The smallest…

The “marine ice-sheet instability” hypothesis continues to be used to interpret the observed mass loss from the Antarctic and Greenland ice sheets. This hypothesis has been developed for conditions that do not account for feedbacks between ice sheets and environmental conditions. However, snow accumulation and the ice-sheet surface melting…

This paper examines the effect of basal topography and strength on the grounding-line position, flux and stability of rapidly-sliding ice streams. It does so by supposing that the buoyancy of the ice stream is small, and of the same order as the longitudinal stress gradient. Making this scaling assumption makes the role of the basal gradient…