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Impacts of spatial heterogeneity of anthropogenic aerosol emissions in a regionally refined global aerosol–climate model
Taufiq Hassan, Kai Zhang, Jianfeng Li, Balwinder Singh, Shixuan Zhang, Hailong Wang, and Po-Lun Ma
Geosci. Model Dev., 17, 3507–3532, https://doi.org/10.5194/gmd-17-3507-2024, 2024
Anthropogenic aerosol emissions are an essential part of global aerosol models. Significant errors can exist from the loss of emission heterogeneity. We introduced an emission treatment that significantly improved aerosol emission heterogeneity in high-resolution model simulations, with improvements in simulated aerosol surface concentrations. The emission treatment will provide a more accurate representation of aerosol emissions and their effects on climate.

HGS-PDAF (version 1.0): a modular data assimilation framework for an integrated surface and subsurface hydrological model
Qi Tang, Hugo Delottier, Wolfgang Kurtz, Lars Nerger, Oliver S. Schilling, and Philip Brunner
Geosci. Model Dev., 17, 3559–3578, https://doi.org/10.5194/gmd-17-3559-2024, 2024
We have developed a new data assimilation framework by coupling an integrated hydrological model HydroGeoSphere with the data assimilation software PDAF. Compared to existing hydrological data assimilation systems, the advantage of our newly developed framework lies in its consideration of the physically based model; its large selection of different assimilation algorithms; and its modularity with respect to the combination of different types of observations, states and parameters.

BOATSv2: New ecological and economic features improve simulations of High Seas catch and effort
Jerome Guiet, Daniele Bianchi, Kim J. N. Scherrer, Ryan F. Heneghan, and Eric D. Galbraith
Geosci. Model Dev. Discuss., https//doi.org/10.5194/gmd-2024-26,2024
Preprint under review for GMD (discussion: open, 0 comments)
Numerical models that capture key features of the global dynamics of fish communities play a crucial role in addressing the impacts of climate change and industrial fishing on ecosystems and societies. Here, we detail an update of the BiOeconomic marine Trophic Size-spectrum model that corrects the model representation of the dynamic of fisheries in the High Seas. This update also allows a better representation of biodiversity to improve future global and regional fisheries studies.

The Real Challenges for Climate and Weather Modelling on its Way to Sustained Exascale Performance: A Case Study using ICON (v2.6.6)
Panagiotis Adamidis, Erik Pfister, Hendryk Bockelmann, Dominik Zobel, Jens-Olaf Beismann, and Marek Jacob
Geosci. Model Dev. Discuss., https//doi.org/10.5194/gmd-2024-54,2024
Preprint under review for GMD (discussion: open, 0 comments)
In this paper, we investigated performance indicators of the climate model ICON on different compute architectures to answer the question of how to generate high resolution climate simulations. Evidently, utilizing more processing units of the conventionally used architectures is not enough, presumably architectures with a larger memory throughput are the most promising way. More potential can be gained from single node optimization rather than simply increasing the number of compute nodes.

An unusual reduction in the strength of Earth's magnetic field between 591 and 565 million years ago coincided with a significant increase in the oxygen levels in the atmosphere and oceans, according to a paper published in Communications Earth & Environment. The authors propose that the weakening of the magnetic field may have led to the increase in oxygen, which is believed to have supported the evolution of some of the earliest complex organisms.

A team of paleoclimatologists with the U.S. Geological Survey, NASA Ames Research Park, has found that atmospheric rivers in the past have dumped far more rain on California than those that have occurred over the past two years.

In early spring, George Okoko was perched on a ledge 15 feet up a crumbly cliff, trying to whack off a basketball-size piece of rock with a hammer and chisel. The locale was suburban Berkeley Heights, N.J. The rock was basalt, a common product of volcanism. This batch formed some 200 million years ago, during vast eruptions that occurred as Europe slowly tore away from North America, creating a chasm that became the Atlantic Ocean.

Climate change is transforming dust storms—a natural phenomenon in the Middle East—into a more frequent and widespread threat to health and economies throughout the region, a new study shows.

Solving a North-type energy balance model using boundary integral methods
Aksel Samuelsberg and Per Kristen Jakobsen
Nonlin. Processes Geophys. Discuss., https//doi.org/10.5194/npg-2024-11,2024
Preprint under review for NPG (discussion: open, 0 comments)
We explored a simplified climate model based on Earth's energy budget. One advantage of such models is that they are easier to study mathematically. Using a mathematical technique known as boundary integral methods, we have found a new way to solve these climate models. This method is particularly useful for modeling climates very different from Earth's current state, such as those on other planets or during past ice ages.

Abstract

Fluids and melts in planetary interiors significantly influence geodynamic processes from volcanism to global-scale differentiation. The roles of these geofluids depend on their viscosities (η). Constraining geofluid η at relevant pressures and temperatures relies on laboratory-based measurements and is most widely done using Stokes' Law viscometry with falling spheres. Yet small sample chambers required by high-pressure experiments introduce significant drag on the spheres. Several correction schemes are available for Stokes' Law but there is no consensus on the best scheme(s) for high-pressure experiments. We completed high-pressure experiments to test the effects of (a) the relative size of the sphere diameter to the chamber diameter and (b) the top and bottom of the chamber, that is, the ends, on the sphere velocities. We examined the influence of current correction schemes on the estimated viscosity using Monte Carlo simulations. We also compared previous viscometry work on various geofluids in different experimental setups/geometries. We find the common schemes for Stokes' Law produce statistically distinct values of η. When inertia of the sphere is negligible, the most appropriate scheme may be the Faxén correction for the chamber walls. Correction for drag due to the chamber ends depends on the precision in the sinking distance and may be ineffective with decreasing sphere size. Combining the wall and end corrections may overcorrect η. We also suggest the uncertainty in η is best captured by the correction rather than propagated errors from experimental parameters. We develop an overlying view of Stokes' Law viscometry at high pressures.

Abstract

Subduction processes play a pivotal role in facilitating material exchange between the crust and mantle, contributing to the growth of continents. However, the onset and evolution of subduction remain hotly debated. Here, we developed a high-dimensional machine learning (ML) model to use multiple compositional data (e.g., Nb/La, Nb, Ti, Nb/U, Pb/Nd, and Nb/Th) to distinguish arc-type from non-arc basalts worldwide, then applied this well-trained ML model to identify and delineate the secular occurrence of Archean arc-type basalts. Our findings indicate that basaltic arc magmatism can be traced back to only a few early Archean cratons. A noticeable increase in the prevalence of arc-type basalts during the Mesoarchean and Neoarchean suggests the synchronous formation of Archean subduction across different cratons. This observation hints at transitioning from the predominantly stagnant geodynamic regime to the early, more mobile tectonic regime.

Abstract

The physical behavior of a falling raindrop is governed by delicate fluid dynamics and thermodynamics, and oscillates with time. Despite this time-variant nature, past observational and simulation studies have aimed to generalize parameterizations for describing rain microphysics bearing the assumption that raindrops fall at terminal speeds with an equilibrium shape. However, the applicability of this hypothesis in a realistic atmosphere that is inherently turbulent remains an open question. Here, we employ novel retrieval techniques to quantify the impact of turbulence on raindrop microphysics using long-term in situ observations with careful assessment of the wind effect. We find that raindrop microphysics increasingly deviate from the equilibrium state as the turbulence dissipation rate increases, and this effect is more pronounced for large raindrops. We present turbulence-invoked rain microphysical parameterizations which shed light on the complex interactions between turbulence dynamics and raindrop microphysics.

Science, Volume 384, Issue 6695, Page 516-516, May 2024.

Science, Volume 384, Issue 6695, Page 517-517, May 2024.

Science, Volume 384, Issue 6695, Page 573-579, May 2024.

Science, Volume 384, Issue 6695, Page 546-551, May 2024.

Science, Volume 384, Issue 6695, Page 551-556, May 2024.

Science, Volume 384, Issue 6695, Page 528-532, May 2024.

Science, Volume 384, Issue 6695, Page 557-563, May 2024.

Science, Volume 384, Issue 6695, Page 563-572, May 2024.