Conditions controlling atmospheric pollutant deposition via snowpack

2010 ◽  
Vol 18 (NA) ◽  
pp. 87-114 ◽  
Author(s):  
Marek Błaś ◽  
Katarzyna Cichała-Kamrowska ◽  
Mieczysław Sobik ◽  
Żaneta Polkowska ◽  
Jacek Namieśnik

Solid precipitation represents a potentially important addition to other measures of deposition. However, an accurate estimate of snowfall amount and pollutant loading is not a trivial matter. There are obvious distinctions between regular precipitation collection and snowpack sampling that represent the cumulative chemistry of bulk deposition. The main goal is to show the most important processes and factors that may influence the rate and magnitude of pollutants deposition affected by the snowfall and snow cover: atmospheric pollutant enhancement of snowfall, pollutants deposition at snow cover surface, drifting and blowing snow, formation of the snow cover and its internal changes, as well as pollutants flow through the snowpack. These phenomena lead to continuous changes in the chemistry of the snow cover and the deposition calculated on the basis of pollutants concentrations in daily portions of atmospheric precipitation. The real deposition released from snowpack is strictly related to the number and depth of thaw episodes. If the amount of stored pollutants is large, first portions of ablation water flushing from the snowpack can carry the load of pollutants, and potentially affecting the environment in a detrimental way. Igneous bedrock is especially sensitive to acidic ions because of its low buffering capacity.

2006 ◽  
Vol 7 (5) ◽  
pp. 984-994 ◽  
Author(s):  
Konosuke Sugiura ◽  
Tetsuo Ohata ◽  
Daqing Yang

Abstract Intercomparison of solid precipitation measurement at Barrow, Alaska, has been carried out to examine the catch characteristics of various precipitation gauges in high-latitude regions with high winds and to evaluate the applicability of the WMO precipitation correction procedures. Five manual precipitation gauges (Canadian Nipher, Hellmann, Russian Tretyakov, U.S. 8-in., and Wyoming gauges) and a double fence intercomparison reference (DFIR) as an international reference standard have been installed. The data collected in the last three winters indicates that the amount of solid precipitation is characteristically low, and the zero-catch frequency of the nonshielded gauges is considerably high, 60%–80% of precipitation occurrences. The zero catch in high-latitude high-wind regions becomes a significant fraction of the total precipitation. At low wind speeds, the catch characteristics of the gauges are roughly similar to the DFIR, although it is noteworthy that the daily catch ratios decreased more rapidly with increasing wind speed compared to the WMO correction equations. The dependency of the daily catch ratios on air temperature was confirmed, and the rapid decrease in the daily catch ratios is due to small snow particles caused by the cold climate. The daily catch ratio of the Wyoming gauge clearly shows wind-induced losses. In addition, the daily catch ratios are considerably scattered under strong wind conditions due to the influence of blowing snow. This result suggests that it is not appropriate to extrapolate the WMO correction equations for the shielded gauges in high-latitude regions for high wind speed of over 6 m s−1.


2002 ◽  
Vol 2 (3/4) ◽  
pp. 147-155 ◽  
Author(s):  
Ch. Jaedicke ◽  
A. D. Sandvik

Abstract. Blowing snow and snow drifts are common features in the Arctic. Due to sparse vegetation, low temperatures and high wind speeds, the snow is constantly moving. This causes severe problems for transportation and infrastructure in the affected areas. To minimise the effect of drifting snow already in the designing phase of new structures, adequate models have to be developed and tested. In this study, snow distribution in Arctic topography is surveyed in two study areas during the spring of 1999 and 2000. Snow depth is measured by ground penetrating radar and manual methods. The study areas encompass four by four kilometres and are partly glaciated. The results of the surveys show a clear pattern of erosion, accumulation areas and the evolution of the snow cover over time. This high resolution data set is valuable for the validation of numerical models. A simple numerical snow drift model was used to simulate the measured snow distribution in one of the areas for the winter of 1998/1999. The model is a two-level drift model coupled to the wind field, generated by a mesoscale meteorological model. The simulations are based on five wind fields from the dominating wind directions. The model produces a satisfying snow distribution but fails to reproduce the details of the observed snow cover. The results clearly demonstrate the importance of quality field data to detect and analyse errors in numerical simulations.


2020 ◽  
Author(s):  
Heidi Hellén ◽  
Simon Schallhart ◽  
Arnaud P. Praplan ◽  
Toni Tykkä ◽  
Mika Aurela ◽  
...  

<p>Wetlands cover an area of about 2% of the total land surface area of the world and are most common in the boreal and tundra zones. Northern wetlands are important sinks for carbon dioxide and sources of methane, but knowledge on their VOC emissions is very limited. Currently, we know that northern wetlands are high isoprene emitters (e.g. Holst et al., 2010), but very little is known on the emissions of other VOCs.</p><p>We have studied VOC emissions and their ambient concentrations at a sub-Arctic wetland (Lompolojänkkä) in Northern Finland, using an in situ TD-GC-MS. For the emission measurements, a dynamic flow-through FEP chamber was used.</p><p>Earlier studies have shown that isoprene is emitted from wetlands and it turned out to be the most abundant compound in the current study also. Monoterpene (MT) emissions were generally less than 10 % of the isoprene emissions, but sesquiterpenes (SQT) emissions were surprisingly high, exceeding MT emissions at all times. Both MT and SQT emissions were dependent on temperature.</p><p>Even with the higher emissions from the wetland, ambient air concentrations of isoprene were clearly lower than MT concentrations. This indicates that wetland was not the only source affecting atmospheric concentrations at the site, but surrounding coniferous forests, which are high MT emitters, contribute as well. In May concentrations of SQTs and MTs at Lompolojänkkä were higher than in earlier boreal forest measurements in southern Finland (Hellén et al., 2018). At that time, the snow cover on the ground was melting and soil thawing and VOCs produced under the snow cover, e.g. by microbes and decaying litter, can be released to the air. Daily mean MT concentrations were very highly negatively correlated with daily mean ozone concentrations indicating that vegetation emissions can be a significant chemical sink of ozone at this sub-Arctic area.</p><p>References</p><p>Hellén, H.et al. 2018, Atmos. Chem. Phys., 18, 13839-13863, https://doi.org/10.5194/acp-18-13839-2018.</p><p>Holst, T., et al. 2010, Atmos. Chem. Phys., 10, 1617-1634, https://doi.org/10.5194/acp-10-1617-2010.</p>


Author(s):  
Inom Normatov ◽  
Parviz Normatov

Abstract. Results of monitoring accumulated snow cover in upstream areas of the Transboundary Pyanj River (Central Asia) are presented. It is found that the formation of the snow cover and the spatial distribution of atmospheric precipitation in the Mountain Pamir is determined by the orography of the terrain. Orography influences air mass movement in mountain areas, which contributes in different climatic zones to a shift in periods when the maximum amount of snow is falling. Completely different scenarios for the development of meteorological variables in the western and eastern parts of the Gunt River Basin were found, due, firstly, to the influence of the mountainous area orography and, secondly, to the penetration of various air masses. It is observed that in the western part of the basin the average annual precipitation remained almost unchanged over the period 1944–2014, whereas there is a decreasing trend in the eastern part. Assessment of the climate change impact on the formation of the Gunt River water flow was made by comparing the trend in the change of discharge using data from two observation periods 1940–1970 and 1986–2016. Calculations show a decrease of the Gunt River discharge by 5 % over a period of more than 70 years. The influence of climate warming on the river flow is indicated by comparison of river hydrograph in two periods 1940–1970 and 1986–2016. The hydrograph of the Vanch River in the earlier-mentioned periods shows a shift in the maximum of the monthly discharge towards the left, indicating an earlier melting of snow and glaciers in the upstream regions of the river and a significant increase in discharge in the period 1986–2016.


2019 ◽  
Vol 17 (1) ◽  
pp. 61-76
Author(s):  
Krzysztof Błażejczyk ◽  
Oleh Skrynyk

Abstract Chornohora is the highest mountain ridge in the Ukrainian Carpathians with 6 peaks of an altitude over 2,000 m above sea level (Hoverla is the highest peak, 2,061 m a.s.l). Its climate is explored less than other mountain ridges in Europe. The massif is a climatic barrier for air masses on NW-SE line. To describe the climate of this area data from the weather station at Pozhyzhevska alpine meadow for the years 1961–2010 were used. The seasonal and long-term variability of air temperature, atmospheric precipitation and snow cover were investigated on the background of air circulation types. The results show that general features of Chornohora climate depend both, on elevation above sea level and on air circulation. Lowest temperature is observed at N-NE circulation and highest precipitation – at western air inflow. Long-term changes of examined climate elements in Chornohora show significant increase in mean (0.13°/10 years) and minimum (0.22°C/10 years) air temperature as well as in snow cover depth and number of snowy days.


2021 ◽  
Author(s):  
Varun Sharma ◽  
Franziska Gerber ◽  
Michael Lehning

<p>When a well-developed, high velocity katabatic flow draining down the ice sheet of Antarctica reaches the coast, it experiences an abrupt and rapid transition due to change in slope resulting in formation of a hydraulic jump. A remarkable manifestation of the hydraulic jump, given the ‘right’ surface conditions, is the large-scale entrainment and convergence of blowing snow particles within the hydraulic jump. This can result in formation of 100-1000 m high, highly localized ‘walls’ of snow in the air in an otherwise cloud-free sky.</p><p>Recent work by Vignon et al. (2020) has described in detail, the mechanisms resulting in the formation of hydraulic jumps and excitation of gravity waves during a particularly notable event at the Dumont d’Urville (DDU) station in August 2017. They used a combination of satellite images, mesoscale simulations with WRF and station measurements (including Micro Rain Radars) in their study, notably relying on the snow wall for diagnosing and quantifying the hydraulic jump in satellite images. On the other hand, relatively less importance was given towards the surface snow processes including the transport of snow particles in the wall.</p><p>In this presentation, we present results from simulations done using the recently developed CRYOWRF v1.0 to recreate the August 2017 episode at DDU and explicitly simulate the formation and the dynamics of the snow wall itself. CRYOWRF enhances the standard WRF model with the state-of-the-art surface snow modelling scheme SNOWPACK as well as a completely new blowing snow scheme. SNOWPACK essentially acts as a land surface model for the WRF atmospheric model, thus making a quantum leap over the existing snow cover models in WRF. Since SNOWPACK is a grain-scale snow model, it allows for the proper formulation of boundary conditions for simulating blowing snow dynamics.</p><p>Results show the formation of the snow wall due to large scale entrainment over a wide area of the ice sheet, the mass balance of the snow wall within the hydraulic jump and finally, the destruction of the snow wall and the ultimate fate of all the entrained snow. We also show results for the influence of the snow wall on the local surface radiation at DDU. Overall, we test the capabilities of CRYOWRF to simulate such a complex phenomenon and highlight possible applications now feasible due the tight coupling of an advanced snow cover model and a multi-scale, non-hydrostatic atmospheric flow solver.</p><p>Reference:</p><p>Vignon, Étienne, Ghislain Picard, Claudio Durán-Alarcón, Simon P. Alexander, Hubert Gallée, and Alexis Berne. " Gravity Wave Excitation during the Coastal Transition of an Extreme Katabatic Flow in Antarctica". <em>Journal of the Atmospheric Sciences</em> 77.4 (2020): 1295-1312. <>.</p>


2013 ◽  
Vol 14 (1) ◽  
pp. 203-219 ◽  
Author(s):  
Eric Brun ◽  
Vincent Vionnet ◽  
Aaron Boone ◽  
Bertrand Decharme ◽  
Yannick Peings ◽  
...  

Abstract The Crocus snowpack model within the Interactions between Soil–Biosphere–Atmosphere (ISBA) land surface model was run over northern Eurasia from 1979 to 1993, using forcing data extracted from hydrometeorological datasets and meteorological reanalyses. Simulated snow depth, snow water equivalent, and density over open fields were compared with local observations from over 1000 monitoring sites, available either once a day or three times per month. The best performance is obtained with European Centre for Medium-Range Weather Forecasts (ECMWF) Interim Re-Analysis (ERA-Interim). Provided blowing snow sublimation is taken into account, the simulations show a small bias and high correlations in terms of snow depth, snow water equivalent, and density. Local snow cover durations as well as the onset and vanishing dates of continuous snow cover are also well reproduced. A major result is that the overall performance of the simulations is very similar to the performance of existing gridded snow products, which, in contrast, assimilate local snow depth observations. Soil temperature at 20-cm depth is reasonably well simulated. The methodology developed in this study is an efficient way to evaluate different meteorological datasets, especially in terms of snow precipitation. It reveals that the temporal disaggregation of monthly precipitation in the hydrometeorological dataset from Princeton University significantly impacts the rain–snow partitioning, deteriorating the simulation of the onset of snow cover as well as snow depth throughout the cold season.


2020 ◽  
Vol 26 (7) ◽  
pp. 62-76
Author(s):  
A. Kirillin ◽  
◽  
M. Zheleznyak ◽  
A. Zhirkov ◽  
I. Misailov ◽  
...  

With the intensive industrial development of South Yakutia, in particular the Elkon mountain range, the natural environment is experiencing an enormous anthropogenic load. To assess the state of the natural environment, it is important to obtain information about its background state before the start of an intensive technogenic impact. Snow cover seems to be the optimal indicator of chemical pollution of atmospheric air and atmospheric precipitation, as it is one of the significant natural factors that form natural conditions. To take effective preventive measures to eliminate severe consequences, reliable data on the characteristics and conditions of snow cover formation are required. The object of research is the Elkon mountain range, located in the northern part of the Aldan-Stanovoy Upland. The subject is the peculiarities of the formation of snow cover in this region. The purpose of the study is to determine the main meteorological parameters and physical characteristics that affect the conditions for the formation of snow cover. A set of methods was used in the study, including snow survey and routine observations of snow parameters in key areas. As a result of the study, new data were obtained on the regional features of the formation of snow cover. The practical focus of the study is to improve the reliability of engineering-geological and geocryological mapping and forecasting environmental changes


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