Australian scientists are getting closer to detecting bushfires in record time, thanks to cube satellites with onboard AI now able to detect fires from space 500 times faster than traditional on-ground processing of imagery.
Pico-Light H2O: intercomparison of in situ water vapour measurements during the AsA 2022 campaign
Mélanie Ghysels, Georges Durry, Nadir Amarouche, Dale Hurst, Emrys Hall, Kensy Xiong, Jean-Charles Dupont, Jean-Christophe Samake, Fabien Frérot, Raghed Bejjani, and Emmanuel D. Riviere
Atmos. Meas. Tech., 17, 3495–3513, https://doi.org/10.5194/amt-17-3495-2024, 2024
A tunable diode laser hygrometer, “Pico-Light H2O”, is presented and its performances are evaluated during the AsA 2022 balloon-borne intercomparison campaign from Aire-sur-l'Adour (France) in September 2022. A total of 15 balloons were launched within the framework of the EU-funded HEMERA project. Pico-Light H2O has been compared in situ with the NOAA Frost Point Hygrometer in the upper troposphere and stratosphere, as well as with meteorological sondes (iMet-4 and M20) in the troposphere.
A new method for estimating megacity NOx emissions and lifetimes from satellite observations
Steffen Beirle and Thomas Wagner
Atmos. Meas. Tech., 17, 3439–3453, https://doi.org/10.5194/amt-17-3439-2024, 2024
We present a new method for estimating emissions and lifetimes for nitrogen oxides emitted from large cities by using satellite NO2 observations combined with wind fields. The estimate is based on the simultaneous evaluation of the downwind plumes for opposing wind directions. This allows us to derive seasonal mean emissions and lifetimes for 100 cities around the globe.
Using a portable FTIR spectrometer to evaluate the consistency of Total Carbon Column Observing Network (TCCON) measurements on a global scale: the Collaborative Carbon Column Observing Network (COCCON) travel standard
Benedikt Herkommer, Carlos Alberti, Paolo Castracane, Jia Chen, Angelika Dehn, Florian Dietrich, Nicholas M. Deutscher, Matthias Max Frey, Jochen Groß, Lawson Gillespie, Frank Hase, Isamu Morino, Nasrin Mostafavi Pak, Brittany Walker, and Debra Wunch
Atmos. Meas. Tech., 17, 3467–3494, https://doi.org/10.5194/amt-17-3467-2024, 2024
The Total Carbon Column Observing Network is a network of ground-based Fourier transform infrared (FTIR) spectrometers used mainly for satellite validation. To ensure the highest-quality validation data, the network needs to be highly consistent. This is a major challenge, which so far is solved by site comparisons with airborne in situ measurements. In this work, we describe the use of a portable FTIR spectrometer as a travel standard for evaluating the consistency of TCCON sites.
A perspective on the next generation of Earth system model scenarios: towards representative emission pathways (REPs)
Malte Meinshausen, Carl-Friedrich Schleussner, Kathleen Beyer, Greg Bodeker, Olivier Boucher, Josep G. Canadell, John S. Daniel, Aïda Diongue-Niang, Fatima Driouech, Erich Fischer, Piers Forster, Michael Grose, Gerrit Hansen, Zeke Hausfather, Tatiana Ilyina, Jarmo S. Kikstra, Joyce Kimutai, Andrew D. King, June-Yi Lee, Chris Lennard, Tabea Lissner, Alexander Nauels, Glen P. Peters, Anna Pirani, Gian-Kasper Plattner, Hans Pörtner, Joeri Rogelj, Maisa Rojas, Joyashree Roy, Bjørn H. Samset, Benjamin M. Sanderson, Roland Séférian, Sonia Seneviratne, Christopher J. Smith, Sophie Szopa, Adelle Thomas, Diana Urge-Vorsatz, Guus J. M. Velders, Tokuta Yokohata, Tilo Ziehn, and Zebedee Nicholls
Geosci. Model Dev., 17, 4533–4559, https://doi.org/10.5194/gmd-17-4533-2024, 2024
The scientific community is considering new scenarios to succeed RCPs and SSPs for the next generation of Earth system model runs to project future climate change. To contribute to that effort, we reflect on relevant policy and scientific research questions and suggest categories for representative emission pathways. These categories are tailored to the Paris Agreement long-term temperature goal, high-risk outcomes in the absence of further climate policy and worlds “that could have been”.
Remote sensing-based high-resolution mapping of the forest canopy height: some models are useful, but might they be even more if combined?
Nikola Besic, Nicolas Picard, Cédric Vega, Lionel Hertzog, Jean-Pierre Renaud, Fajwel Fogel, Agnès Pellissier-Tanon, Gabriel Destouet, Milena Planells-Rodriguez, and Philippe Ciais
Geosci. Model Dev. Discuss., https//doi.org/10.5194/gmd-2024-95,2024
Preprint under review for GMD (discussion: open, 0 comments)
The creation of advanced mapping models for forest attributes, utilizing remote sensing data and incorporating machine or deep learning methods, has become a key area of interest in the domain of forest observation and monitoring. This paper introduces a method where we blend and collectively interpret five models dedicated to estimating forest canopy height. We achieve this through Bayesian model averaging, offering a comprehensive approach to height estimation in forest ecosystems.
Abstract
Fungal aerosols, as significant biocomponents of inhalable particulate matter, encompass a variety of allergens and pathogens. However, comprehensive knowledge regarding their composition, sources, and opportunistic pathogens present in severe air pollution remains limited. In this study, PM2.5 samples were collected from January to March 2018 in a northern Chinese city, during the winter heating and spring sandstorm seasons. The fungal community characteristics within three distinct haze and haze-dust composite pollution were examined. The concentration of fungal aerosols was found to be significantly higher in dust samples. This was evidenced by a strong positive correlation with Ca2+, temperature, and wind speed (p < 0.05). Human and animal pathogens, such as Candida, were more prevalent in haze samples. Conversely, allergens and plant pathogens, like Alternaria, were found in higher concentration in dust samples. The primary ecological function shifted from being saprophytic to becoming human-animal pathogenic or plant-animal pathogenic. This shift was observed from non-pollution, haze, to haze-dust composite pollution. The dispersion of fungal aerosols was influenced by factors such as dust events and meteorological conditions, including increased temperature and wind speed. In the spring dust episodes, dust-related pollutants, such as soil Ca2+ and PM10, accounted for 51.39% of the variation in the fungal community. This research explored the dynamics of fungal communities, potential pathogens, and factors influencing fungal communities in regional air pollution. The insights garnered from this research provide a robust foundation for subsequent human health exposure assessments.
Abstract
The formation of secondary organic aerosol (SOA) is inextricably linked to the photo-oxidation of aromatic hydrocarbons. However, models still exhibit biases in representing SOA mass and chemical composition. We implemented a box model coupled with a near-explicit photochemical mechanism, the Master Chemical Mechanism (MCMv3.3.1), to simulate a series of chamber studies and assess model biases in simulating SOA from representative monocyclic aromatic hydrocarbons, that is, toluene and three xylene isomers (TX SOA). The box model underpredicted SOA yields of toluene and xylenes by 4.7%–100%, which could be improved by adjusting the saturation vapor pressure (SVP) of their oxidation products. After updating the SVP values, the mass concentration of TX SOA in the Yangtze River Delta region during summer doubled, and there was also an approximate 3% enhancement in the total SOA. Compared to a lumped mechanism used for simulating TX SOA, MCM predicted comparable mass concentrations but exhibited different volatility distributions and oxidation states.
A new study finds climate change is likely to make upward spikes of ozone at ground level worse by 2050, which could result in many parts of the United States falling out of compliance with air quality standards and increasing risks to public health.
Data from the pair of CubeSats will offer new insights into how much heat the Arctic and Antarctica radiate into space and how this influences global climate.
Beneath the roar of gunfire and the chaos of D-day, an unlikely hero played a vital role—wetland science. Often overlooked amid military strategies and troop movements, the study of mud proved critical to the success of the largest amphibious invasion in history.
Software sustainability of global impact models
Emmanuel Nyenah, Petra Döll, Daniel S. Katz, and Robert Reinecke
Geosci. Model Dev. Discuss., https//doi.org/10.5194/gmd-2024-97,2024
Preprint under review for GMD (discussion: open, 1 comment)
Research software is crucial for scientific progress but is often developed by scientists with limited training, time, and funding, leading to software that is hard to understand, (re)use, modify, and maintain. Our study across 10 research sectors highlights strengths in version control, open-source licensing, and documentation while emphasizing the need for containerization and code quality. Recommendations include workshops, code quality metrics, funding, and adherence to FAIR standards.
Short-term effects of hurricanes on nitrate-nitrogen runoff loading: a case study of Hurricane Ida using E3SM land model (v2.1)
Yilin Fang, Hoang Viet Tran, and L. Ruby Leung
Geosci. Model Dev. Discuss., https//doi.org/10.5194/gmd-2024-70,2024
Preprint under review for GMD (discussion: open, 0 comments)
Hurricanes may worsen the water quality in the lower Mississippi River Basin (LMRB) by increasing nutrient runoff. We found that runoff parameterizations greatly affect nitrate-nitrogen runoff simulated using an Earth system land model. Our simulations predicted increased nitrogen runoff in LMRB during Hurricane Ida in 2021, but less pronounced than the observations, indicating areas for model improvement to better understand and manage nutrient runoff loss during hurricanes in the region.
In a recent publication in Nature Communications, researchers have uncovered significant interactions in sea surface temperature (SST) variations between the Western Australian coast and the western-central tropical Pacific.
By taking a close look at the geometrical makeup of rocks where earthquakes originate, researchers at Brown University are adding a new wrinkle to a long-held belief about what causes seismic quakes in the first place.
California relies on its rivers and streams for a plethora of services—water supply, flood control, biodiversity conservation, and hydropower generation, to name a few. As a result, understanding the flow of water through the state's stream network is critical for supporting California's economy and ecosystems.
A team of computer scientists at Microsoft Research AI for Science, working with a colleague from JKU Linz, another from Poly Corporation, and another from the University of Amsterdam, has built what Microsoft describes in its press release, as a "cutting-edge foundation model"—a system called Aurora that can be used to make global weather and air pollution level predictions more quickly than traditional systems.
Ice shelves surrounding Antarctica have been melting with increasing speed in recent years. Much of this melting happens from below, as warm water eats away at their bases. This warm water is moved around Antarctica by currents that remain only partially understood because of the continent's vastness and remoteness. Mapping these currents in better detail will improve understanding of the future of the continent's mantle of ice.
Abstract
The capabilities of assimilating the all-sky Fengyun-4A Advanced Geostationary Radiation Imager (AGRI) infrared radiances (IR) are completed by including hydrometers in the observation operator, its adjoint, and tangent linear model. This allows the three-dimensional variational data assimilation model to include cloud-precipitation information from infrared IR observations. Advanced as the all-sky data assimilation methodologies are, the assimilation of cloudy scene IR radiances for tropical cyclone (TC) systems has not led to consistently better results, especially for the intensity of TCs. This work explores the effects of all-sky AGRI radiance assimilation on a Super Typhoon In-Fa (2106) during its stage experiencing abnormal changes in the intensity and the track. It is shown that the all-sky assimilation of AGRI two channels 9–10 brings no obviously better TC forecasts than the all-sky AGRI single-channel assimilation does. Besides, the O − B (observation minus background) bias was corrected to be even larger with the variational bias correction method for the pixels with relatively lower or higher cloud impact. This indicates that traditional bias correction schemes with linear fitting functions are suboptimal if the relations between the predictor and O − B biases are non-linear. When the conventional observation and IR radiances are assimilated in two steps, the wind in the inner-core region is better described to properly capture the changes in the typhoon intensity. Generally, the analyses and forecasts of Typhoon In-Fa from experiments with the all-sky IR observations are enhanced compared to those with only the clear-sky IR observations.
Abstract
Observational evidence has shown that the Earth's tropics have widened since 1980. However, climate models underestimate the observed tropical expansion rate, with a large spread among individual models. The proposal of internal variability to account for model–observation differences is hindered by the limited availability of sufficient realizations from models in the Coupled Model Intercomparison Project (CMIP), restricting the accuracy of quantitative contribution estimation. The emergence of a single model initial-condition large ensemble provides a new opportunity to quantify the role of internal variability. Here, using large-ensemble simulations from two individual models complemented with CMIP Phase 6 (CMIP6) simulations, we show evidence that the recent widening of the tropics is mainly caused by internal variability related to the Interdecadal Pacific Oscillation (IPO). The positive-to-negative phase transition of the IPO from 1980 to 2014 reduced the meridional tropospheric temperature gradient, resulting in poleward shifts in tropical edges. After adjusting the IPO trends simulated by individual realizations to ensure consistency with the observations, the IPO phase transition can account for at least 73% (66%) of the observed tropical expansion rate in the Northern Hemisphere based on the metric of the meridional stream function (surface zonal wind). The IPO is also essential for shaping tropical expansion-related precipitation changes. Our results underscore the significance of considering internal variability when explaining model–observation differences and understanding intermodel uncertainty.
