scholarly journals Air–sea exchanges of CO<sub>2</sub> in the world's coastal seas

2013 ◽  
Vol 10 (10) ◽  
pp. 6509-6544 ◽  
Author(s):  
C.-T. A. Chen ◽  
T.-H. Huang ◽  
Y.-C. Chen ◽  
Y. Bai ◽  
X. He ◽  
...  
Keyword(s):  
Wind Speed ◽  
Water Temperature ◽  
Unit Area ◽  
Co2 Flux ◽  
The Arctic ◽  
Lower Latitude ◽  
High Pco2 ◽  
Wind Speeds ◽  
Continental Shelves ◽  
Major Factors

Abstract. The air–sea exchanges of CO2 in the world's 165 estuaries and 87 continental shelves are evaluated. Generally and in all seasons, upper estuaries with salinities of less than two are strong sources of CO2 (39 ± 56 mol C m−2 yr−1, positive flux indicates that the water is losing CO2 to the atmosphere); mid-estuaries with salinities of between 2 and 25 are moderate sources (17.5 ± 34 mol C m−2 yr−1) and lower estuaries with salinities of more than 25 are weak sources (8.4 ± 14 mol C m−2 yr−1). With respect to latitude, estuaries between 23.5 and 50° N have the largest flux per unit area (63 ± 101 mmol C m−2 d−1); these are followed by lower-latitude estuaries (23.5–0° S: 44 ± 29 mmol C m−2 d−1; 0–23.5° N: 39 ± 55 mmol C m−2 d−1), and then regions north of 50° N (36 ± 91 mmol C m−2 d−1). Estuaries south of 50° S have the smallest flux per unit area (9.5 ± 12 mmol C m−2 d−1). Mixing with low-pCO2 shelf waters, water temperature, residence time and the complexity of the biogeochemistry are major factors that govern the pCO2 in estuaries, but wind speed, seldom discussed, is critical to controlling the air–water exchanges of CO2. The total annual release of CO2 from the world's estuaries is now estimated to be 0.10 Pg C yr−1, which is much lower than published values mainly because of the contribution of a considerable amount of heretofore unpublished or new data from Asia and the Arctic. The Asian data, although indicating high pCO2, are low in sea-to-air fluxes because of low wind speeds. Previously determined flux values rely heavily on data from Europe and North America, where pCO2 is lower but wind speeds are much higher, such that the CO2 fluxes are higher than in Asia. Newly emerged CO2 flux data in the Arctic reveal that estuaries there mostly absorb rather than release CO2. Most continental shelves, and especially those at high latitude, are undersaturated in terms of CO2 and absorb CO2 from the atmosphere in all seasons. Shelves between 0 and 23.5° S are on average a weak source and have a small flux per unit area of CO2 to the atmosphere. Water temperature, the spreading of river plumes, upwelling, and biological production seem to be the main factors in determining pCO2 in the shelves. Wind speed, again, is critical because at high latitudes, the winds tend to be strong. Since the surface water pCO2 values are low, the air-to-sea fluxes are high in regions above 50° N and below 50° S. At low latitudes, the winds tend to be weak, so the sea-to-air CO2 flux is small. Overall, the world's continental shelves absorb 0.4 Pg C yr−1 from the atmosphere.

scholarly journals <i>Review article</i> "Air-sea exchanges of CO<sub>2</sub> in world's coastal seas"

2013 ◽  
Vol 10 (3) ◽  
pp. 5041-5105 ◽  
Author(s):  
C.-T. A. Chen ◽  
T.-H. Huang ◽  
Y.-C. Chen ◽  
Y. Bai ◽  
X. He ◽  
...  
Keyword(s):  
Wind Speed ◽  
Water Temperature ◽  
Unit Area ◽  
Co2 Flux ◽  
The Arctic ◽  
Wind Speeds ◽  
Continental Shelves ◽  
Low Latitudes ◽  
Major Factors ◽  
Negative Flux

Abstract. The air-sea exchanges of CO2 in the world's 165 estuaries and 87 continental shelves are evaluated. Generally and in all seasons, upper estuaries with salinities of less than two are strong sources of CO2 (39 &amp;pm; 56 mol C m−2 yr−1, negative flux indicates that the water is losing CO2 to the atmosphere); mid-estuaries with salinities of between 2 and 25 are moderate sources (17.5 ± 34 mol C m−2 yr−1) and lower estuaries with salinities of more than 25 are weak sources (8.4 ± 14 mol C m−2 yr−1). With respect to latitude, estuaries between 23.5 and 50° N have the largest flux per unit area (63 ± 101 mmol C m−2 d−1); these are followed by mid-latitude estuaries (23.5–0° S: 44 ± 29 mmol C m−2 d−1; 0–23.5° N: 39 ± 55 mmol C m−2 d−1), and then regions north of 50° N (36 ± 91 mmol C m−2 d−1). Estuaries south of 50° S have the smallest flux per unit area (9.5 ± 12 molC m−2 d−1). Mixing with low-pCO2 shelf waters, water temperature, residence time and the complexity of the biogeochemistry are major factors that govern the pCO2 in estuaries but wind speed, seldom discussed, is critical to controlling the air-water exchanges of CO2. The total annual release of CO2 from the world's estuaries is now estimated to be 0.10 PgC yr−1, which is much lower than published values mainly because of the contribution of a considerable amount of heretofore unpublished or new data from Asia and the Arctic. The Asian data, although indicating high in pCO2, are low in sea-to-air fluxes because the wind speeds are lower than previously determined values, which rely heavily on data from Europe and North America, where pCO2 is lower but wind speeds are much higher, such that the CO2 fluxes are higher than in Asia. Newly emerged CO2 flux data in the Arctic reveal that estuaries there mostly absorb, rather than release CO2. Most continental shelves, and especially those at high latitude, are under-saturated in terms of CO2 and absorb CO2 from the atmosphere in all seasons. Shelves between 0° and 23.5° S are on average a weak source and have a small flux per unit area of CO2 to the atmosphere. Water temperature, the spreading of river plumes, upwelling, and biological production seem to be the main factors in determining pCO2 in the shelves. Wind speed, again, is critical because at high latitudes, the winds tend to be strong. Since the surface water pCO2 values are low, the air-to-sea fluxes are high in regions above 50° N and below 50° S. At low latitudes, the winds tend to be weak, so the sea-to-air CO2 flux is small. Overall, the world's continental shelves absorb 0.4 PgC yr−1 from the atmosphere.

scholarly journals Atmospheric Circulation Effects on Wind Speed Variability at Turbine Height

2007 ◽  
Vol 46 (4) ◽  
pp. 445-456 ◽  
Author(s):  
Katherine Klink
Keyword(s):  
Wind Speed ◽  
Pressure Gradient ◽  
Large Scale ◽  
Ground Level ◽  
The Arctic ◽  
Circulation Index ◽  
Regression Equations ◽  
Change Models ◽  
Wind Speeds ◽  
The North

Abstract Mean monthly wind speed at 70 m above ground level is investigated for 11 sites in Minnesota for the period 1995–2003. Wind speeds at these sites show significant spatial and temporal coherence, with prolonged periods of above- and below-normal values that can persist for as long as 12 months. Monthly variation in wind speed primarily is determined by the north–south pressure gradient, which captures between 22% and 47% of the variability (depending on the site). Regression on wind speed residuals (pressure gradient effects removed) shows that an additional 6%–15% of the variation can be related to the Arctic Oscillation (AO) and Niño-3.4 sea surface temperature (SST) anomalies. Wind speeds showed little correspondence with variation in the Pacific–North American (PNA) circulation index. The effect of the strong El Niño of 1997/98 on the wind speed time series was investigated by recomputing the regression equations with this period excluded. The north–south pressure gradient remains the primary determinant of mean monthly 70-m wind speeds, but with 1997/98 removed the influence of the AO increases at nearly all stations while the importance of the Niño-3.4 SSTs generally decreases. Relationships with the PNA remain small. These results suggest that long-term patterns of low-frequency wind speed (and thus wind power) variability can be estimated using large-scale circulation features as represented by large-scale climatic datasets and by climate-change models.

Investigation of weather conditions and tropospheric BrO transport during Bromine Explosion Events in the Arctic and ozone depletion in Ny-Ålesund observed by satellite and ground-based remote sensing

2021 ◽  
Author(s):  
Bianca Zilker ◽  
Anne-Marlene Blechschmidt ◽  
Sora Seo ◽  
Ilias Bougoudis ◽  
Tim Bösch ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Detection Limit ◽  
Wind Speed ◽  
Ozone Depletion ◽  
Weather Conditions ◽  
Tropospheric Chemistry ◽  
The Arctic ◽  
Blowing Snow ◽  
High Wind ◽  
Wind Speeds

&lt;p align=&quot;justify&quot;&gt;Bromine Explosion Events (BEEs) have been observed since the late 1990s in the Arctic and Antarctic during polar spring and play an important role in tropospheric chemistry. In a heterogeneous, autocatalytic, chemical chain reaction cycle, inorganic bromine is released from the cryosphere into the troposphere and depletes ozone often to below detection limit. Ozone is a source of the most important tropospheric oxidizing agent OH and the oxidizing capacity and radiative forcing of the troposphere are thus being impacted. Bromine also reacts with gaseous mercury, thereby facilitating the deposition of toxic mercury, which has adverse environmental impacts. C&lt;span lang=&quot;en-US&quot;&gt;old saline surfaces, such as young sea ice, frost flowers, and snow are likely bromine sources &lt;/span&gt;&lt;span lang=&quot;en-US&quot;&gt;during BEEs. &lt;/span&gt;&lt;span lang=&quot;en-US&quot;&gt;D&lt;/span&gt;ifferent meteorological conditions seem to favor the development of these events: on the one hand, low wind speeds and a stable boundary layer, where bromine can accumulate and deplete ozone, and on the other hand, high wind speeds above approximately 10 m/s with blowing snow and a higher unstable boundary layer. In high wind speed conditions &amp;#8211; occurring for example along fronts of polar cyclones &amp;#8211; recycling of bromine on snow and aerosol surfaces may take place aloft.&lt;/p&gt; &lt;p align=&quot;justify&quot;&gt;To improve the understanding of weather conditions and bromine sources leading to the development of BEEs, case studies using high resolution S5P TROPOMI retrievals of tropospheric BrO together with meteorological simulations by the WRF model and Lagrangian transport simulations of BrO by FLEXPART-WRF are carried out. WRF simulations show, that high tropospheric BrO columns observed by TROPOMI often coincide with areas of high wind speeds. This probably points to release of bromine from blowing snow with cold temperatures favoring the bromine explosion reactions. However, some BrO plumes are observed over areas with very low wind speed and a stable low boundary layer. To monitor the amount of ozone depleted during a BEE, ozone sonde measurements from Ny-&amp;#197;lesund are compared with MAX-DOAS BrO profiles. First evaluations show a drastic decrease in ozone, partly below the detection limit, while measuring enhanced BrO values at the same time. &lt;span lang=&quot;en-US&quot;&gt;In order to analyze &lt;/span&gt;&lt;span lang=&quot;en-US&quot;&gt;the possible origin&lt;/span&gt;&lt;span lang=&quot;en-US&quot;&gt; of the BrO &lt;/span&gt;&lt;span lang=&quot;en-US&quot;&gt;plume &lt;/span&gt;&lt;span lang=&quot;en-US&quot;&gt;arriving in &lt;/span&gt;&lt;span lang=&quot;en-US&quot;&gt;Ny-&lt;/span&gt;&lt;span lang=&quot;en-US&quot;&gt;&amp;#197;&lt;/span&gt;&lt;span lang=&quot;en-US&quot;&gt;lesund&lt;/span&gt;&lt;span lang=&quot;en-US&quot;&gt;, &lt;/span&gt;&lt;span lang=&quot;en-US&quot;&gt;and to investigate its transportation route, &lt;/span&gt;&lt;span lang=&quot;en-US&quot;&gt;FLEXPART-WRF runs are &lt;/span&gt;&lt;span lang=&quot;en-US&quot;&gt;executed &lt;/span&gt;&lt;span lang=&quot;en-US&quot;&gt;for the times of observed ozone depletion.&lt;/span&gt;&lt;/p&gt; &lt;p align=&quot;justify&quot;&gt;&amp;#160;&lt;/p&gt; &lt;p align=&quot;justify&quot;&gt;&lt;em&gt;This work was supported by the&lt;/em&gt;&lt;em&gt; DFG funded Transregio-project TR 172 &amp;#8220;Arctic Amplification &lt;/em&gt;(AC)&lt;sup&gt;3&lt;/sup&gt;&lt;em&gt;&amp;#8220;.&lt;/em&gt;&lt;/p&gt;

scholarly journals Soil moisture, wind speed and depth hoar formation in the Arctic snowpack

2018 ◽  
Vol 64 (248) ◽  
pp. 990-1002 ◽  
Author(s):  
FLORENT DOMINE ◽  
MARIA BELKE-BREA ◽  
DENIS SARRAZIN ◽  
LAURENT ARNAUD ◽  
MATHIEU BARRERE ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Soil Moisture ◽  
Wind Speed ◽  
Thermal Conditions ◽  
High Arctic ◽  
Water Vapor Transport ◽  
The Arctic ◽  
Vegetation Growth ◽  
Wind Speeds ◽  
Strong Winds

ABSTRACTBasal depth hoar that forms in Arctic snowpacks often has a low thermal conductivity, strongly contributing to the snowpack thermal insulance and impacting the permafrost thermal regime. At Ward Hunt Island (Canadian high Arctic, 83°05′N, 74°07′W) almost no depth hoar was observed in spring 2016 despite favorable thermal conditions. We hypothesize that depth hoar formation was impeded by the combination of two factors (1) strong winds in fall that formed hard dense wind slabs where water vapor transport was slow and (2) low soil moisture that led to rapid ground cooling with no zero-curtain period, which reduced soil temperature and the temperature gradient in the snowpack. Comparisons with detailed data from the subsequent winter at Ward Hunt and from Bylot Island (73°09′N, 80°00′W) and with data from Barrow and Alert indicate that both high wind speeds after snow onset and low soil moisture are necessary to prevent Arctic depth hoar formation. The role of convection to form depth hoar is discussed. A simple preliminary strategy to parameterize depth hoar thermal conductivity in snow schemes is proposed based on wind speed and soil moisture. Finally, warming-induced vegetation growth and soil moisture increase should reduce depth hoar thermal conductivity, potentially affecting permafrost temperature.

Variability of the Intermediate Atlantic Water of the Arctic Ocean over the Last 100 Years

2004 ◽  
Vol 17 (23) ◽  
pp. 4485-4497 ◽  
Author(s):  
I. V. Polyakov ◽  
G. V. Alekseev ◽  
L. A. Timokhov ◽  
U. S. Bhatt ◽  
R. L. Colony ◽  
...  
Keyword(s):  
Water Temperature ◽  
Arctic Ocean ◽  
Observational Data ◽  
Low Frequency ◽  
Atlantic Water ◽  
The Arctic ◽  
Lower Latitude ◽  
Complex Nature ◽  
Temperature Record ◽  
The Arctic Ocean

Abstract Recent observations show dramatic changes of the Arctic atmosphere–ice–ocean system, including a rapid warming in the intermediate Atlantic water of the Arctic Ocean. Here it is demonstrated through the analysis of a vast collection of previously unsynthesized observational data, that over the twentieth century Atlantic water variability was dominated by low-frequency oscillations (LFO) on time scales of 50–80 yr. Associated with this variability, the Atlantic water temperature record shows two warm periods in the 1930s–40s and in recent decades and two cold periods earlier in the century and in the 1960s–70s. Over recent decades, the data show a warming and salinification of the Atlantic layer accompanied by its shoaling and, probably, thinning. The estimate of the Atlantic water temperature variability shows a general warming trend; however, over the 100-yr record there are periods (including the recent decades) with short-term trends strongly amplified by multidecadal variations. Observational data provide evidence that Atlantic water temperature, Arctic surface air temperature, and ice extent and fast ice thickness in the Siberian marginal seas display coherent LFO. The hydrographic data used support a negative feedback mechanism through which changes of density act to moderate the inflow of Atlantic water to the Arctic Ocean, consistent with the decrease of positive Atlantic water temperature anomalies in the late 1990s. The sustained Atlantic water temperature and salinity anomalies in the Arctic Ocean are associated with hydrographic anomalies of the same sign in the Greenland–Norwegian Seas and of the opposite sign in the Labrador Sea. Finally, it is found that the Arctic air–sea–ice system and the North Atlantic sea surface temperature display coherent low-frequency fluctuations. Elucidating the mechanisms behind this relationship will be critical to an understanding of the complex nature of low-frequency variability found in the Arctic and in lower-latitude regions.

scholarly journals Sea Spray Generation at a Rocky Shoreline

2016 ◽  
Vol 55 (9) ◽  
pp. 2037-2052 ◽  
Author(s):  
Edgar L Andreas
Keyword(s):  
Wind Speed ◽  
Surf Zone ◽  
Open Water ◽  
High Energy ◽  
Offshore Structures ◽  
The Arctic ◽  
Sea Spray ◽  
Near Surface ◽  
Marginal Seas ◽  
Wind Speeds

AbstractWith sea ice in the Arctic continuing to shrink, the Arctic Ocean and the surrounding marginal seas will become more like the ocean at lower latitudes. In particular, with more open water, air–sea exchange will be more intense and storms will be stronger and more frequent. The longer fetches over open water and the more energetic storms will combine to produce higher waves and more sea spray. Offshore structures—such as oil drilling, exploration, and production platforms—will face increased hazards from freezing sea spray. On the basis of sea spray observations made with a cloud-imaging probe at Mount Desert Rock (an island off the coast of Maine), the spray that artificial islands built in the Arctic might experience is quantified. Mount Desert Rock is small, low, and unvegetated and has an abrupt, rocky shoreline like these artificial islands might have. Many of the observations were at air temperatures below freezing. This paper reports the near-surface spray concentration and the rate of spray production at this rocky shoreline for spray droplets with radii from 6.25 to 143.75 μm and for wind speeds from 5 to 17 m s−1. Spray concentration increases as the cube of the wind speed, but the shape of the concentration spectrum with respect to radius does not change with wind speed. Both near-surface spray concentration and the spray-production rate are three orders of magnitude higher at this rocky shoreline than over the open ocean because of the high energy and resulting continuous white water in the surf zone.

Metabolic response to wind of downy chicks of Arctic-breeding shorebirds(Scolopacidae)

2002 ◽  
Vol 205 (22) ◽  
pp. 3435-3443 ◽  
Author(s):  
George S. Bakken ◽  
Joseph B. Williams ◽  
Robert E. Ricklefs
Keyword(s):  
Wind Speed ◽  
Air Temperature ◽  
Heat Production ◽  
Metabolic Response ◽  
Evaporative Cooling ◽  
Thermal Conductance ◽  
The Arctic ◽  
Evaporative Water ◽  
Near Surface ◽  
Wind Speeds

SUMMARYWind is a significant factor in the thermoregulation of chicks of shorebirds on the Arctic tundra. We investigated the effect of wind at speeds typical of near-surface conditions (0.1-3 ms-1) on metabolic heat production, evaporative cooling and thermal conductance of 1- to 3- week-old downy scolopacid chicks (least sandpiper Calidris minutilla;short-billed dowitcher Limnodromus griseus; whimbrel Numenius phaeopus). Body mass ranged from 9 to 109 g. To accurately measure the interacting effects of air temperature and wind speed, we used two or more air temperatures between 15° and 30°C that produced cold stress at all wind speeds, but allowed chicks to maintain normal body temperature(approximately 39°C). Thermal conductance increased by 30-50% as wind speed increased from 0.1 to 3 ms-1. Conductance in these chicks is somewhat lower than that of 1-day-old mallard ducklings of similar mass, but higher than values reported for downy capercaillie and Xantus' murrelet chicks, as well as for adult shorebirds. Evaporative water loss was substantial and increased with mass and air temperature. We developed a standard operative temperature scale for shorebird chicks. The ratio of evaporative cooling to heat production varied with wind speed and air temperature.

scholarly journals Future Trends of Arctic Surface Wind Speeds and their Relationship with Sea Ice in CMIP5 Climate Model Simulations

2021 ◽  
Author(s):  
Stephen Vavrus ◽  
Ramdane Alkama
Keyword(s):  
Surface Roughness ◽  
Wind Speed ◽  
Sea Ice ◽  
Surface Wind ◽  
Ice Cover ◽  
The Arctic ◽  
Future Trends ◽  
Surface Winds ◽  
Wind Speeds ◽  
Arctic Surface

Abstract Recent climate change in the Arctic has been rapid and dramatic, leading to numerous physical and societal consequences. Many studies have investigated these ongoing and projected future changes across a range of climatic variables, but surprisingly little attention has been paid to wind speed, despite its known importance for sea ice motion, ocean wave heights, and coastal erosion. Here we analyzed future trends in Arctic surface wind speed and its relationship with sea ice cover among CMIP5 global climate models. There is a strong anticorrelation between climatological sea ice concentration and wind speed in the early 21 st -century reference climate, and the vast majority of models simulate widespread future strengthening of surface winds over the Arctic Ocean (annual multi-model mean trend of up to 0.8 m s -1 or 13%). Nearly all models produce an inverse relationship between projected changes in sea ice cover and wind speed, such that grid cells with virtually total ice loss almost always experience stronger winds. Consistent with the largest regional ice losses during autumn and winter, the greatest increases in future wind speeds are expected during these two seasons, with localized strengthening up to 23%. As in other studies, stronger surface winds cannot be attributed to tighter pressure gradients but rather to some combination of weakened atmospheric stability and reduced surface roughness as the surface warms and melts. The intermodel spread of wind speed changes, as expressed by the two most contrasting model results, appears to stem from differences in the treatment of surface roughness.

scholarly journals Drivers of Atmosphere-Ocean CO2 Flux in Northern Norwegian Fjords

2021 ◽  
Vol 8 ◽  
Author(s):  
Nerea J. Aalto ◽  
Karley Campbell ◽  
Hans C. Eilertsen ◽  
Hans C. Bernstein
Keyword(s):  
Surface Water ◽  
High Latitude ◽  
Co2 Flux ◽  
Subsurface Water ◽  
Study Region ◽  
Instantaneous Rate ◽  
Carbon Regulation ◽  
Wind Speeds ◽  
Continental Shelves ◽  
Coastal Bay

High-latitude fjords and continental shelves are shown to be sinks for atmospheric CO2, yet large spatial-temporal variability and poor regional coverage of sea-air CO2 flux data, especially from fjord systems, makes it difficult to scale our knowledge on how they contribute to atmospheric carbon regulation. The magnitude and seasonal variability of atmosphere-sea CO2 flux was investigated in high-latitude northern Norwegian coastal areas over 2018 and 2019, including four fjords and one coastal bay. The aim was to assess the physical and biogeochemical factors controlling CO2 flux and partial pressure of CO2 in surface water via correlation to physical oceanographic and biological measurements. The results show that the study region acts as an overall atmospheric CO2 sink throughout the year, largely due to the strong undersaturation of CO2 relative to atmospheric concentrations. Wind speed exerted the strongest influence on the instantaneous rate of sea-air CO2 exchange, while exhibiting high variability. We concluded that the northernmost fjords (Altafjord and Porsangerfjord) showed stronger potential for instantaneous CO2 uptake due to higher wind speeds. We also found that fixation of CO2 was likely a significant factor controlling ΔpCO2 from April to June, which followed phenology of spring phytoplankton blooms at each location. Decreased ΔpCO2 and the resulting sea-air CO2 flux was observed in autumn due to a combined reduction of the mixed layer with entrain of high CO2 subsurface water, damped biological activity and higher surface water temperatures. This study provides the first measurements of atmospheric CO2 flux in these fjord systems and therefore an important new baseline for gaining a better understanding on how the northern Norwegian coast and characteristic fjord systems participate in atmosphere carbon regulation.

scholarly journals Downslope windstorms and associated extreme wind speed statistics evaluation according to the COSMO-CLM Russian Arctic hindcast, ASR reanalysis and observations

2021 ◽  
Author(s):  
Vladimir Platonov ◽  
Anna Shestakova
Keyword(s):  
Wind Speed ◽  
Surface Wind ◽  
Temperature Fields ◽  
The Arctic ◽  
Russian Arctic ◽  
Novaya Zemlya ◽  
Wind Speeds ◽  
Extreme Wind ◽  
Extreme Wind Speed ◽  
Downslope Windstorms

&lt;p&gt;The number of severe weather events at the Arctic region increased significantly. Its formation related generally to the mesoscale processes including downslope windstorms over Novaya Zemlya, Svalbard, Tiksi bay accompanied by strong winds. Therefore, its investigation required detailed hydrometeorological and climatic information with a horizontal resolution of at least several kilometers. This work aims to investigate extreme wind speeds statistics associated with downslope windstorms and evaluate it according to the COSMO-CLM Russian Arctic hindcast, ASR reanalysis, stations and satellite data.&lt;/p&gt;&lt;p&gt;COSMO-CLM Russian Arctic hindcast created in 2020 covers the 1980&amp;#8211;2016 period with grid size ~12 km and 1-hour output step, containing approximately a hundred hydrometeorological characteristics, as well at surface, as on the 50 model levels. The primary assessments of the surface wind speed and temperature fields showed good agreement with ERA-Interim reanalysis in large-scale patterns and many added values in the regional mesoscale features reproduction according to the coastlines, mountains, large lakes, and other surface properties.&lt;/p&gt;&lt;p&gt;Mean values, absolute and daily maxima of wind speed, high wind speed frequencies were estimated for the COSMO-CLM Russian Arctic hindcast and the well-known Arctic System Reanalysis (ASRv2) for a 2000-2016 period. COSMO-CLM showed higher mean and daily maximal wind speed areas concerned to coastal regions of Svalbard and Scandinavia, over the northern areas of Taymyr peninsula. At the same time, the absolute wind speed maxima are significantly higher according to ASRv2, specially over the Barents Sea, near the Novaya Zemlya coast (differences are up to 15-20 m/s). The same pattern observed by a number of days with wind speed above the 30 m/s threshold. Compared with station data, the ASRv2 reproduced mean wind speeds better at most coastal and inland station, MAE are within 3 m/s. For absolute wind speed maxima differences between two datasets get lower, the COSMO-CLM hindcast is quite better for inland stations.&lt;/p&gt;&lt;p&gt;Model capability to reproduce strong downslope windstorms evaluated according to the observations timeseries over Novaya Zemlya, Svalbard and Tiksi stations during bora conditions. Generally, the ASRv2 reproduced the wind direction closer to observations and the wind speed worser than COSMO-CLM. The extreme wind speed frequencies during bora cases have less errors according to COSMO-CLM hindcast (up to ~5%) compared to the ASRv2 data (up to 10%). At the same time, moderate wind speed frequencies are reproduced by ASRv2 better.&lt;/p&gt;&lt;p&gt;Five specific Novaya Zemlya bora cases were evaluated according to SAR satellite wind speed data. Both ASRv2 and COSMO-CLM overestimated mean wind speed (MAE 0.5-6 m/s), maximal wind speed bias has different signs, however, the COSMO-CLM is better in most cases. Extreme percentiles biases (99 and 99.9%), correlation, structure and amplitude (according to the SAL method) are closer to observations by the COSMO-CLM hindcast.&lt;/p&gt;

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