27 research outputs found
Seasonal impact analysis on population due to continuous sulphur emissions from severonikel smelters of the Kola Peninsula
cited By 0This study is devoted to investigation of total deposition and loading patterns for population of the North-West Russia and Scandinavian countries due to continuous emissions (following âmild emission scenarioâ) of sulphates from the Cu-Ni smelters (Severonikel enterprise, Murmansk region, Russia). The Lagrangian long-range dispersion model (Danish Emergency Response Model for Atmosphere) was run in a long-term mode to simulate atmospheric transport, dispersion and deposition over the Northern Hemisphericâs domain north of 10°N, and results were integrated and analyzed in the GIS environment. Analysis was performed on annual and seasonal scales, including depositions, impact on urban areas and calculating individual and collective loadings on population in selected regions of Russia and Scandinavian countries. It was found that wet deposition dominates, and it is higher in winter. The North-West Russia is more influenced by the Severonikel emissions compared with the Scandinavian countries. Among urban areas, the Russian cities of Murmansk (due to its proximity to the source) and Arkhangelsk (due to dominating atmospheric flows) are under the highest impact. The yearly individual loadings on population are the largest (up to 120 kg/person) for the Murmansk region; lower (15 kg/person) for territories of the northern Norway, and the smallest (less than 5 kg/person) for the eastern Finland, Karelia Republic, and Arkhangelsk region. These loadings have distinct seasonal variability with a largest contribution during winter-spring for Russia, spring â for Norway, and autumn â for Finland and Sweden; and the lowest during summer (i.e. less than 10 and 1 kg/person for the Russia and Scandinavian countries, respectively). The yearly collective loadings for population living on the impacted territories in Russia, Finland, Norway, and Sweden are 2628, 140.4, 13, and 10.7 tonnes, respectively. Š 2018, Lomonosov Moscow State University. All rights reserved.Peer reviewe
Two-timescale carbon cycle response to an AMOC collapse
Atmospheric CO2 concentrations (pCO2) varied on millennial timescales in phase with Antarctic temperature during the last glacial period. A prevailing view has been that carbon release and uptake by the Southern Ocean dominated this millennialâscale variability in pCO2. Here, using Earth System Model experiments with an improved parameterization of ocean vertical mixing, we find a major role for terrestrial and oceanic carbon releases in driving the pCO2 trend. In our simulations, a change in Northern Hemisphere insolation weakens the Atlantic Meridional Overturning Circulation (AMOC) leading to increasing pCO2 and Antarctic temperatures. The simulated rise in pCO2 is caused in equal parts by increased CO2 outgassing from the global ocean due to a reduced biological activity and changed ventilation rates, and terrestrial carbon release as a response to southward migration of the Intertropical Convergence Zone. The simulated terrestrial release of carbon could explain stadial declines in organic carbon reservoirs observed in recent ice core δ13C measurements. Our results show that parallel variations in Antarctic temperature and pCO2 do not necessitate that the Southern Ocean dominates carbon exchange; instead, changes in carbon flux from the global ocean and land carbon reservoirs can explain the observed pCO2 (and δ13C) changes
Online integrated modeling on regional scale in North-West Russia: Evaluation of aerosols influence on meteorological parameters
In this study the aerosols influence on selected meteorological parameters during two summer 2010 periods is evaluated with focus on the North-West Russia and urban area of St. Petersburg. For that, the seamless fully online-integrated Enviro-HIRLAM model is used. The simulations are realised in short-and long-term modes for selected periods. For evaluation of aerosol influence, in addition to the control/ reference run, the runs with direct, indirect and both combined aerosol effects are performed. It was found that for the North-West Russia region, the direct aerosol effect had increased air temperature (by 1-3Ë) and decreased total cloud cover (by 10-20%). The indirect effect decreased temperature (by 0.4-1Ë) and increased cloud cover (by 10-20%). The combined effect was the largest territorially; and such effect both decreased temperature and cloud cover (by 1-3Ë and by 6-20%, respectively) as well as increased these (by 0.4-0.6Ë and 10-20%). Š 2018, Lomonosov Moscow State University. All rights reserved.Peer reviewe
Downscaling system for modeling of atmospheric composition on regional, urban and street scales
In this study, the downscaling modeling chain for prediction of weather and atmospheric composition is described and evaluated against observations. The chain consists of interfacing models for forecasting at different spatiotemporal scales that run in a semi-operational mode. The forecasts were performed for European (EU) regional and Danish (DK) subregional-urban scales by the offline coupled numerical weather prediction HIRLAM and atmospheric chemical transport CAMx models, and for Copenhagen citystreet scale by the online coupled computational fluid dynamics M2UE model. The results showed elevated NOx and lowered O-3 concentrations over major urban, industrial, and transport land and water routes in both the EU and DK domain forecasts. The O-3 diurnal cycle predictions in both these domains were equally good, although O-3 values were closer to observations for Denmark. At the same time, the DK forecast of NOx and NO2 levels was more biased (with a better prediction score of the diurnal cycle) than the EU forecast, indicating a necessity to adjust emission rates. Further downscaling to the street level (Copenhagen) indicated that the NOx pollution was 2-fold higher on weekends and more than 5 times higher during the working day with high pollution episodes. Despite high uncertainty in road traffic emissions, the street-scale model effectively captured the NOx and NO2 diurnal cycles and the onset of elevated pollution episodes. The demonstrated downscaling system could be used in future online integrated meteorology and air quality research and operational forecasting, as well as for impact assessents on environment, population, and decision making for emergency preparedness and safety measures planning.Peer reviewe
Veros v0.1 â a fast and versatile ocean simulator in pure Python
A
general circulation ocean model is translated from Fortran to Python. Its
code structure is optimized to exploit available Python utilities, remove
simulation bottlenecks, and comply with modern best practices. Furthermore, support for
Bohrium is added, a framework that provides a just-in-time compiler for array
operations and that supports parallel execution on both CPU and GPU targets.For applications containing more than a million grid elements, such as a
typical 1°âĂâ1° horizontal resolution global ocean model,
Veros is approximately half as fast as the MPI-parallelized Fortran base code
on 24Â CPUs and as fast as the Fortran reference when running on a high-end
GPU. By replacing the original conjugate gradient stream function solver with
a solver from the pyAMG Python package, this particular subroutine
outperforms the corresponding Fortran version by up to 1 order of magnitude.The study is concluded with a simple application in which the North Atlantic
wave response to a Southern Ocean wind perturbation is investigated. It is
found that even in a realistic setting the phase speeds of boundary waves
matched the expectations based on theory and idealized models.</p
Enviro-HIRLAM online integrated meteorology-chemistry modelling system: strategy, methodology, developments and applications (v7.2)
This is the final version. Available on open access from the European Geosciences Union via the DOI in this recordCode and data availability. The Enviro-HIRLAM modelling system is a community model. The source code is available for
non-commercial use (i.e. research, development and science education) upon agreement through contact with Bent Hansen
Sass ([email protected]) and Roman Nuterman ([email protected]).
Documentation, educational materials and practical exercises are
available from http://hirlam.org and http://hirlam.org/index.php/
documentation/chemistry-branch, and YSSS training schools (http:
//netfam.fmi.fi/YSSS08, http://www.ysss.osenu.org.ua and http://
aveirosummerschool2014.web.ua.pt).The Environment â High Resolution Limited Area Model (Enviro-HIRLAM) is developed as a fully online integrated numerical weather prediction (NWP) and atmospheric chemical transport (ACT) model for research and forecasting of joint meteorological, chemical and biological weather. The integrated modelling system is developed by the Danish Meteorological Institute (DMI) in collaboration with several European universities. It is the baseline system in the HIRLAM Chemical Branch and used in several countries and different applications. The development was initiated at DMI more than 15 years ago. The model is based on the HIRLAM NWP model with online integrated pollutant transport and dispersion, chemistry, aerosol dynamics, deposition and atmospheric composition feedbacks. To make the model suitable for chemical weather forecasting in urban areas, the meteorological part was improved by implementation of urban parameterisations. The dynamical core was improved by implementing a locally mass-conserving semi-Lagrangian numerical advection scheme, which improves forecast accuracy and model performance. The current version (7.2), in comparison with previous versions, has a more advanced and cost-efficient chemistry, aerosol multi-compound approach, aerosol feedbacks (direct and semi-direct) on radiation and (first and second indirect effects) on cloud microphysics. Since 2004, the Enviro-HIRLAM has been used for different studies, including operational pollen forecasting for Denmark since 2009 and operational forecasting atmospheric composition with downscaling for China since 2017. Following the main research and development strategy, further model developments will be extended towards the new NWP platform â HARMONIE. Different aspects of online coupling methodology, research strategy and possible applications of the modelling system, and fit-for-purpose model configurations for the meteorological and air quality communities are discussed
Description of the CEEH integrated "Energy-Environment-Health-Cost" modelling franework system
THE MUST MODEL EVALUATION EXERCISE: STATISTICAL ANALYSIS OF MODELLING RESULTS
The first validation exercise of the COST action 732 lead to a substantial number of simulation results for comparison
with the MUST wind tunnel experiments. Validation metrics for selected simulation results of the flow field and the concentrations
are presented and compared to the state of the art. In addition mean metrics and corresponding scatter limits are computed from the
individual results
THE MUST MODEL EVALUATION EXERCISE: PATTERNS IN MODEL PERFORMANCE
As part of the COST 732 action more than a dozen different research groups have modelled the MUST experiment, as
simulated in a wind tunnel. The model evaluation guidance developed within COST 732 recommends \u27exploratory data analysis\u27 as
one of the elements in model validation. Experience has shown that such exploratory analysis is crucial to reveal shortcomings of
models that might otherwise pass unnoticed. Conditions are best for detecting common patterns and anomalies if you have a
situation where several models are put into a common framework â like the case at hand. The available material provides a unique
opportunity to identify and explore patterns within model performance