ITS2.11/AS4.12

Pollen grains emitted from vegetation can release subpollen particles (SPP) that contribute to the fine fraction of atmospheric aerosols and may act as cloud condensation nuclei (CCN), ice nuclei (IN), or aeroallergens. Here, we investigate and characterize the hygroscopic growth and CCN activation of birch, pine, and rapeseed SPP. A high humidity tandem differential mobility analyzer (HHTDMA) was used to measure particle restructuring and water uptake over a wide range of relative humidity (RH) from 2 % to 99.5 %, and a continuous flow CCN counter was used for size-resolved measurements of CCN activation at supersaturations (S) in the range of 0.2 % to 1.2 %. For both subsaturated and supersaturated conditions, effective hygroscopicity parameters к , were obtained by Köhler model calculations. Gravimetric and chemical analyses, electron microscopy, and dynamic light scattering measurements were performed to characterize further properties of SPP from aqueous pollen extracts such as chemical composition (starch, proteins, DNA, and inorganic ions) and the hydrodynamic size distribution of water-insoluble material. All investigated SPP samples exhibited a sharp increase of water uptake and k above ~95 % RH, suggesting a liquid-liquid phase separation (LLPS). The HHTDMA measurements at RH> 95% enable closure between the CCN activation at water vapor supersaturation and hygroscopic growth at subsaturated conditions, which is often not achieved when HTDMA measurements are performed at lower RH where the water uptake and effective hygroscopicity may be limited by the effects of LLPS. Such effects may be important not only for closure between hygroscopic growth and CCN activation but also for the chemical reactivity, allergenic potential, and related health effects of SPP.

This research has been supported by the Russian Science Foundation (grant no. 18-10 17-00076) and Max Planck Society.

How to cite: Mikhailov, E., Pöhlker, M., Reinmuth-Selzle, K., Vlasenko, S., Pöhlker, C., Ivanova, O., and Pöschl, U.: Water uptake of subpollen aerosol particles: hygroscopic growth, CCN activation, and liquid-liquid phase separation, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-7901, https://doi.org/10.5194/egusphere-egu21-7901, 2021.

Black carbon is a short - living climate forcer, it plays a significant role especially in the Arctic environment due to heating the atmosphere and changing the radiation balance while depositing on snow and ice. Analysis of black carbon (BC) in the Arctic atmosphere shows a contribution of anthropogenic combustion of fossil fuels and natural wildfires to the Arctic atmosphere chemistry as well as of the main characteristics of Arctic aerosol pollution. Presently, assessments of the environment and climate change in the Siberian Arctic are strongly complicated by an existing lack of knowledge about emission sources, quantity, and composition of the aerosol pollution defining the impacts on an Arctic ecosystem.

Research aerosol station is firstly installed on island Bely located in Kara sea, Siberian Arctic. It takes place on the pathway of air mass from the Northern Siberia region of high anthropogenic and gas flaring activity to the Arctic. Presently, assessments of the environment and climate change in this region are strongly complicated by an existing lack of knowledge about emission sources, quantity and composition of the aerosol pollution defining the impacts on an Arctic ecosystem. Aethalometer and aerosol sampling system is continuously operated on the aerosol station in order to analyze black carbon and chemical characteristics including ionic and elemental composition. Annual BC trend obtained from august 2019 to September 2020 shows the typical Arctic aerosol tendency of a seasonal variability, disturbed by episodes of large-scale emission transportation.

Unprecedented high BC is observed in September 2020 at the research aerosol station on the island Bely. The BC concentrations early in September were exceeded 20 times the arctic background. They are found to be even higher than the highest arctic haze concentrations observed in December 2019.   Monthly averaged black carbon concentration in September 2020 exceeded 3 times that one in previous summer months. Such strong event is a result of large-scale air mass transportation from Eurasian continent in the period of strong wildfires in western Siberia, namely in Krasnoyarsk Kray and Yakutia, where around one million hectares of forest were burned out in August 2020. 

Basic researches of aerosol characteristics as a tracer of anthropogenic emissions are supported by Russian Fond for Basic Research, project №18-60084.

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How to cite: Popovicheva, O., Kobelev, V., Chichaeva, M., Kasimov, N., and Hansen, A.: Сlimate-active aerosol components in the Siberian Arctic, by data from new-developed research aerosol station on island Bely, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-6302, https://doi.org/10.5194/egusphere-egu21-6302, 2021.

The Arctic is warming much faster than other regions of the globe. In 2020, temperature anomalies in the Russian Arctic reached unprecedented high levels. The atmospheric composition in this key region still remains insufficiently studied that makes difficult predicting future climate change.

In September 2020, an extensive aircraft campaign was conducted to document the tropospheric composition over the Russian Arctic. The Optik Tu-134 research aircraft was equipped with instruments to carry out in-situ measurements of trace gases and aerosols, as well as with a lidar for profiling of aerosol backscatter. The aircraft flew over a vast area from Arkhangelsk to Anadyr. Six measurement flights with changing altitudes from 0.2 to 9.0 m were conducted over the waters of the Barents, Kara, Laptev, East Siberian, Chukchi, and Bering Seas. The weather was unusually warm for this period of the year, surface air temperatures were above 0°C through the campaign.

Here, we present the results of in-situ measurements of the vertical distribution of aerosol number concentrations in a wide range of sizes. A modified diffusional particle sizer (DPS) consisted of the Novosibirsk-type eight-stage screen diffusion battery connected to the TSI condensation particle counter Model 3756 was used to determine the number size distribution of particles between 0.003 mm and 0.2 mm (20 size bins). Distribution of particles in the size range from 0.25 µm to 32 µm (31 size bins) was measured by means of the Grimm aerosol spectrometer Model 1.109.

The flights over Barents and Kara Seas were predominantly performed under clear sky or partly cloudy weather conditions. Number size distributions were wide representing particles of almost all aerosol fractions. When flying in the upper troposphere with a constant altitude over these seas, some cases of enhanced concentrations of nucleation and Aitken mode particles comparable to ones in the lower troposphere were recorded, suggesting in situ new particle formation was likely to be taking place via gas-to-particle conversion aloft.

East of the Kara Sea, flights were conducted under mostly cloudy conditions resulting in a lower median aerosol number concentration and narrower size distributions.

This work was supported by the Russian Foundation for Basic Research (Grant No. 19-05-50024).

How to cite: Arshinov, M. Yu., Belan, B., Davydov, D., Kozlov, A., and Fofonov, A.: Vertical distribution of aerosol particles over the Russian Arctic derived from in-situ aircraft measurements: the September 2020 campaign, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-6909, https://doi.org/10.5194/egusphere-egu21-6909, 2021.

In 2020, a unique experiment, which had ever been implemented either in the former USSR or in modern-day Russia, was carried out in the Russian Arctic by means of the Optik Tu-134 aircraft laboratory operated by IAO SB RAS. The airborne measurement campaign was conducted on September 4-17 over all seas and coastal regions of the Russian sector of the Arctic, including northern part of the Bering Sea.

During the flights, in situ measurements of CO, CO₂, CH₄, NO, NO₂, SO₂, O₃, aerosols, and black carbon (BC) were performed. Air samples were taken to determine organic and inorganic compounds and biological material in aerosol particles. A remote sensing of the water turbidity in the upper sea layers was conducted by means of the LOZA-2 lidar that allowed a concentration of plankton to be derived there. Spectral characteristics of the water and underlying coastal surfaces were measured using a spectroradiometer.

The primary analysis of the obtained data showed that concentrations of CO, NO, NO₂, SO₂, O₃, aerosols, and BC during the experiment were low that is typical for background regions. CO₂ mixing ratios in the lowest part of the troposphere above seas were lower than aloft. As compared with coastal areas, concentration of methane over all the seas of the Arctic sector and the Bering Sea was higher.

We would like to acknowledge our colleagues from the following organizations for their assistance in organizing and conducting this campaign, and in particular, Laboratoire des sciences du climat et de l'environnement and Laboratoire atmosphères, milieux, observations spatiales (France); Finnish Meteorological Institute and Institute for Atmospheric and Earth System Research, University of Helsinki (Finland); Center for Global Environmental Research at the National Institute for Environmental Studies (Japan); the National Oceanic and Atmospheric Administration, US Department of Commerce (USA); Max-Planck-Institute for Biochemistry (Germany); and University of Reading (UK).

How to cite: Belan, B. D., Antokhin, P., Antokhina, O., Arshinova, V., Arshinov, M., Belan, S., Davydov, D., Ivlev, G., Kozlov, A., Kozlov, A., Okhlopkova, O., Rasskazchikova, T., Savkin, D., Safatov, A., Simonenkov, D., Tolmachev, G., and Fofonov, A.: Vertical distribution of trace gases and aerosols over the Russian Arctic in September 2020, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-6892, https://doi.org/10.5194/egusphere-egu21-6892, 2021.

Climate change is proceeding fastest in the Arctic region. While human-induced emissions of long-lived greenhouse gases are the main driving factor of global warming, short-lived climate forcers or pollutants emitted from the forest fires are also playing an important role, especially in the Arctic. Forest fire emissions also affect local air quality and photochemical processes in the atmosphere. For example, CO contributes to the formation of tropospheric ozone and affects the abundance of greenhouse gases such as methane and CO2.

During past years Arctic summers have been warmer and drier elevating the risk for extensive forest fire episodes. Satellite observations show, that during the past three summers (2018-2020) fire detections in Arctic, especially in Arctic Siberia have increased considerably, affecting also local emissions of CO. This work focuses on studying CO concentration and its variation at high latitudes and in the Arctic using satellite and ground-based observations. Satellite observations of CO from TROPOMI are analyzed for the 2018-2020 (NH) summer months. To assess the satellite retrieved columns the satellite measurements are compared to ground-based remote sensing measurements at Sodankylä. Also, ground-based in-situ measurements are used to see how the total column changes mirror the ground level concentrations. The fire characteristics are analyzed using observations from MODIS instruments onboard Aqua and Terra. Fire effects on seasonal cycle and interannual variability of CO concentrations at Arctic high latitudes are analyzed.

How to cite: Karppinen, T., Sundström, A.-M., Lindqvist, H., and Tamminen, J.: Satellite-based analysis of CO and Fires in the Arctic, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-16490, https://doi.org/10.5194/egusphere-egu21-16490, 2021.

Ground-based spectroscopic international measurement systems TCCON and NDACC are important for regular obtaining the data on atmospheric gas composition. A great part of such data is derived as the total content of the gases and as an averaged mixing ratio for the dry atmosphere as, for example, XCO₂. On the other hand, the measurements of solar IR radiation spectra with high spectral resolution carry within them some amount of information on the vertical structure of the content of some gases. The method of estimation of CO₂ content in the troposphere and stratosphere was described in a study [Timofeyev Yu.M., Nerobelov G.M., Poberovskii A.V., Filippov N.N. Evaluation of CO₂ content in troposphere and stratosphere by ground-based IR method.  “Izvestiya, Atmospheric and Oceanic Physics”. 2021, Nо.2]. In our work we present the analysis of the inaccuracies of the suggested approach using different spectral windows. Also, we demonstrate the comparison between CO₂ tropospheric and stratospheric content obtained by the suggested approach using ground-based measurements of IR spectra with high resolution in Peterhof (2009-2019), by Copernicus Atmosphere Monitoring Service (CAMS) and by satellite measurements of XCO₂ in the troposphere and stratosphere using ACE instrument.

How to cite: Timofeyev, Y., Nerobelov, G., Poberovskii, A., and Filippov, N.: Estimation of the tropospheric and stratospheric CO2 content by ground-based IR technique, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-1477, https://doi.org/10.5194/egusphere-egu21-1477, 2021.

How to cite: Panov, A., Prokushkin, A., Lavrič, J., Kübler, K., Korets, M., Urban, A., Sidenko, N., Zrazhevskaya, G., Bondar, M., and Heimann, M.: Accurate continuous observations of carbon dioxide and methane dry mole fractions in the arctic atmosphere near the Dikson settlement, Siberia, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-9773, https://doi.org/10.5194/egusphere-egu21-9773, 2021.

Wildfires remain among the most challenging problems in Ukraine. Each year numerous cases of open burning contribute to huge carbon emissions and turn into forest fires. Using the Global Fire Emissions Database (GFED4), there were studied an average burned fraction in Ukraine, which equals of about 0.2-0.3. 90% of wildfires appeared on agricultural lands. The total contribution to carbon emissions is 0.2-1.0 g·m²·month^-1 with the increasing trend of about 1-2 g·m²·month^-1 per decade. There are three periods with the highest carbon emissions: April, July-August and September-October. While a summer maximum is corresponding to unfavorable temperature and moisture regimes, the main reason of wildfires in spring and autumn is the agricultural open burning. Based on the Sentinel-5P data, it was found that wildfires significantly change the seasonality of carbon monoxide (CO) variations. If maximal CO content is mainly observed in winter at the end of the heating season, in Ukraine the highest CO values continue to exist in April until the open burning stops and the resulting forest fires are extinguished. Wildfires caused the CO content increase to 4.0–5.0 mol·m^-2 which is comparable to the most polluted Ukrainian industrial cities. As a result, air quality deterioration observed at the distances more than 200 km from the burned areas. Using the Enviro-HIRLAM simulations, there were estimated black carbon (BC) distribution, which showed elevated content within the lowest 3-km layer. BC content reaches 600 ppbm near the active fires, 150 ppbm at the distance up to 100 km and 30 ppbm at the distance of about 200-500 km.

How to cite: Savenets, M. and Pysarenko, L.: The impact of wildfires in Ukraine on carbon flux and air quality changes by carbon-containing compounds, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-329, https://doi.org/10.5194/egusphere-egu21-329, 2021.

Across the Arctic, human settlements are challenged by rapid climate change and a broad range of environmental transformations. Some of them, such as Barrow (Utqiagvik, Alaska), must relocate; others, such as Norilsk (Russia), must restructure and rebuild. This presentation reports on local climate anomalies in 118 circum-Arctic cities and towns. For several key towns, a nexus review of the environmental consequences of the local warm anomalies is detailed. Longyearbyen (Svalbard), Apatity and Nadym (Russia) are in focus. For instance, Longyearbyen – the European “gate” to the Arctic – experiences one of the stongest climate change. The surface air temperature here has increased by almost 10^oC over the last 100 years with more than 100 consecutive months being warmer than normal. Snowfall increases threatening with hazardous slab snow avalanches. The last extreme heat wave (July, 2020) showed temperatures up to +21^oC and massive flooding in the coal mine.  This study synthesizes observational evidence of the climate change in the town from a local perspective. We relate meteorological conditions with sustainability issues. The study looks at local climate diversity and its role for society and economy of the settlement.

How to cite: Esau, I. and the SERUS team: A local climate perspective from Arctic towns, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-681, https://doi.org/10.5194/egusphere-egu21-681, 2021.

The growing content of greenhouse gases (GHGs) influences the radiation balance of the planet causing the rise of air temperature in lower atmosphere. This circumstance triggers researchers to create and develop the new methods of estimation of anthropogenic CO₂ emissions. One of such method is top-down estimation which is based on measurements and chemical transport modelling. Since the errors of the top-down approach depend on quality of the modelled data it requires validation by complex observations. In current study we investigated the performance of regional numerical weather prediction and chemistry transport model WRF-Chem and CAMS service in simulating spatio-temporal variation of near surface atmospheric CO₂ mixing ratio in March and April 2019 for the Saint-Petersburg area (Russia). To validate the modelled data, we used local observations obtained on Peterhof (St. Petersburg) station. The analysis demonstrates that WRF-Chem model can adequate simulate the transport of CO₂ in near-surface layer with spatial resolution of 3 km. Average difference and correlation coefficient are in range 0.8-1.6% and 0.55-0.72 respectively. It was found that the WRF-Chem modelled data where biogenic and anthropogenic fluxes were considered fit the observation data worse than the WRF-Chem simulation where only anthropogenic emissions were used. It can be linked to the errors of the biogenic flux calculation. However, to prove that investigations for two contrast periods (in summer and winter) are needed. Despite the rude spatial resolution of the CAMS data (approximately 200x400 km) we found that in general the trend of surface atmospheric CO₂ mixing ratio in March and April 2019 for the Saint-Petersburg area from the CAMS dataset fits the observations.

How to cite: Nerobelov, G., Timofeyev, Y., Smyshlyaev, S., Foka, S., Mammarella, I., and Virolainen, Y.: Validation of the capability of WRF-Chem model and CAMS to simulate near surface atmospheric CO2 mixing ratio for the territory of Saint-Petersburg, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-1497, https://doi.org/10.5194/egusphere-egu21-1497, 2021.

Climate change is one of the major challenges for future development in every country including Ukraine where actual warming already has impacted many sectors, population, and ecosystems. Recently, the International Initiative of Coordinated Downscaling Experiment for Europe (Euro-CORDEX) has provided RCM data for 0.1^o grid. This detailed RCM projection dataset is an excellent basis for estimation of exposure and vulnerability to climate change of different objects and for updating projections for a new National Communication of Ukraine to UNFCCC as well as for Strategy of Ecological Safety and Adaptation to Climate Change in Ukraine.

The study is focused on the estimation of the essential and special climatic characteristics and their changes in the near future (2021-2040) as well as to the middle (2041-2050) and end (2081-2100) of the century over the base period 1991-2010 for three scenarios: RCP2.6, RCP4.5, and RCP8.5. We used bias-adjusted RCM data for daily maximum, mean, and minimum temperature and precipitation provided via ESGF web-portal. We applied a multi-model ensemble approach with further bias-correction by delta-method for multi-year monthly values of the essential characteristics as well as calculated climatic indices using a gridded observational dataset of E-Obs v.20.0e. Ensembles for RCP4.5 and RCP8.5 consisted of 34 RCMs while for RCP2.6 only data of 3 RCMs were available. That is why RCP2.6 is only indicative, while the other two scenarios results have a high confidence level and quartiles and percentiles of the ensemble range are estimated.

More consistent temporally and spatially results were obtained for temperature projections. Increases relative to the baseline were in the range of 0.5-1.5ºC for all the RCPs with a bit higher warming in the North of the country in 2021-2040. In 2041-2060, the increases were 1.0-2.0ºC under RCP2.6 and 1.5-2.5ºC under RCP8.5, with RCP4.5 in between. By the end of the century 2081-2100 the differences between scenarios became much pronounced: from 1-2ºC for RCP2.6 to 4-6ºC for RCP8.5.

Precipitation changes are much complex with high variability across the seasons and the territory. In winter precipitation tends to increase relative to the baseline in most of the country for all the RCPs. In early spring (March) there is a relative decline in the near-future period, especially in RCP2.6 and RCP8.5 but not in RCP4.5. In later periods the decline becomes less and in the higher RCPs, there is a relative increase. Later spring rainfall changes show a decline in RCP2.6 but an increase for the other RCPs. The summer months show a relative decline with all the higher RCPs getting drier over time. In the fall relative changes are mixed, with declines in some months and increases in others.

Based on these two essential climatic characteristics other important indices were calculated and analyzed: length of vegetation season, tropical nights, summer days, water deficit, aridity/humidity index, etc.

Obtained projections of climatic characteristics were(will be) used for further agriculture, forest, and human health impact assessments, that will be the basis for the development of adaptation measures to climate change in the frames of the National Adaptation Plan of Ukraine.  

How to cite: Krakovska, S., Balabukh, V., Chyhareva, A., Pysarenko, L., Trofimova, I., and Shpytal, T.: Projections of regional climate change in Ukraine based on multi-model ensembles of Euro-CORDEX, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-13821, https://doi.org/10.5194/egusphere-egu21-13821, 2021.

New Particle Formation (NPF) is a process in which a large number of particles is formed in the atmosphere via gas-to-particle conversion. Previous research shows the important role of formation of new particles for atmosphere, clouds and climate (Kerminen, V.-M. et al. 2018).

              There exist measurements from different parts of the world which show that NPF is happening worldwide (Kerminen, V.-M. et al. 2018). Measurements at SMEAR II station in Hyytiälä, Finland (Hari P. and Kulmala M., 2005), show that NPF is a common process in Finland’s boreal forests. However, measurements at Zotto station in Siberia, Russia, show that NPF events are very rare in that area (Wiedensohler A. et al., 2018). Measurements in Siberian boreal forests are sparse. We have conducted new measurements at Fonovaya station near Tomsk (Siberia, Russia) using Neutral cluster Air Ion Spectrometer (NAIS), Particle Size Magnifier (PSM), Differential Mobility Particle Sizer (DMPS) and the Atmospheric Pressure interface Time-Of-Flight mass spectrometer (APi-TOF). Those instruments measure aerosol particle number size distribution (NAIS, DMPS), ion number size distribution (NAIS), size distribution of small particles (PSM) and chemical composition of aerosol particles (APi-TOF). The novelty of this work is that such complex measurements have not been done in Siberia before.

              Here we report the first results of our research on NPF phenomenon in Siberian boreal forest. We present detailed statistics of NPF events, as well as formation rates (J) and growth rates (GR) of aerosol particles. The results from Fonovaya station are compared with those from SMEAR II station and from SMEAR Estonia station in Järvselja, Estonia.

Literature

• [1] Kerminen V.-M. et al. “Atmospheric new particle formation and growth: review of field observations”. In: Environmental Research Letters 10 (2018), p. 103003.
• [2] Wiedensohler A. et al. “Infrequent new particle formation over the remote boreal forest of Siberia”. In: Atmospheric Environment 200 (2019), pp. 167–169.
• [3] Dada L. et al. “Long-term analysis of clear-sky new particle formation events and nonevents in Hyytiälä”. In: Atmospheric Chemistry and Physics 10 (2017), pp. 6227–6241.

How to cite: Demakova, A., Garmash, O., Ezhova, E., Arshinov, M., Davydov, D., Belan, B., Noe, S., Komsaare, K., Vana, M., Junninen, H., Bianchi, F., Dada, L., Petäjä, T., Kerminen, V.-M., and Kulmala, M.: Formation and growth of aerosol particles in boreal forest of Siberia, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-14353, https://doi.org/10.5194/egusphere-egu21-14353, 2021.

The world is changing. The polar regions are critical component in the Earth system and influenced by on-going megatrends, such as globalization and demographical changes. The extensive use of Arctic natural resources will have effects on regional pollutant concentrations in the Arctic. We set up the ERA-PLANET Strand 4 project “iCUPE – integrative and Comprehensive Understanding on Polar Environments” to provide novel insights and observational data on global grand challenges with a polar focus. We deploy an integrated approach with in-situ observations, satellite remote sensing and multi-scale modeling to synthesize data from a suite of comprehensive long-term measurements, intensive campaigns, and satellites. This enabled us to deliver novel data and indicators descriptive of the polar environment. The iCUPE framework includes thematic state-of-the-art research and the provision of novel data in atmospheric pollution, local sources and transboundary transport, characterization of arctic surfaces and their changes, an assessment of the concentrations and impacts of heavy metals and persistent organic pollutants and their cycling, the quantification of emissions from natural resource extraction, and the validation and optimization of satellite Earth observation data streams. Here we summarize the project results and provide novel insights into continuation of the work. 

How to cite: Petäjä, T. and the iCUPE team: Integrative and Comprehensive Understanding on Polar Environments (iCUPE) – concept, results and outlook, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-14824, https://doi.org/10.5194/egusphere-egu21-14824, 2021.

The climate change of the last decades has to be reflected in the ecosystems dynamics. By investigating the ecosystem dynamics one can get the information about climate change. One of the most suitable source of information about ecosystem dynamics is remote sensing satellite data. We used EOS multispectral images, gravimetric data of the GRACE satellite, and AURA satellite contents of sulfur dioxide data for the period of the last ~20 years. Daily and 8 days composites of different quantitative characteristics, reduced to the spatial resolution 1x1 km, were retrieved from standard products and raw data: - the daily averaged land surface temperature; - the duration of vegetation (the period of year when a land surface temperature is higher than +10^oC); - the Enhanced Vegetation Index (EVI); - the effective water layer thickness (EWLT) according satellite gravimentry); - the concentration of sulphur dioxide in atmosphere. The speed of each characteristics change was estimated and mapped by using linear regression. As the result, the regular chain of isometric domains of land surface temperature rising and decreasing was noticed from the West edge to the East edge of Northern Eurasia. The presence of this chain was the reason to express hypothesis about more complex structure of the modern atmospheric circulation and interaction between the Ferrel and the Polar cells. Additionally we have noticed that domain of the land surface temperature growth at the Northern part of West Siberia coincides with decreasing of EWLT. We interpreted this phenomena as result of permafrost degradation.

How to cite: Gornyy, V., Kiselev, A., Kritsuk, S., Latypov, I., and Tronin, A.: Multiyear Dynamics of Remotely Mapped Characteristics of Ecosystems in Northern Eurasia, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-3090, https://doi.org/10.5194/egusphere-egu21-3090, 2021.

Transition of arctic vegetation from tundra to shrubs and forest is an important process influencing global carbon budget. Transition is predicted due to warming and prolongation of the growing season but observations show that it is slower than expected. Fires are disturbances that could trigger a shift of biomes.

We studied the transition of dry tundra to forest and woodland in northwest Siberia for burned and background sites within the time interval of 60 years. We used meteorological data to estimate potential shifts in vegetation based on a bioclimatic model. To investigate fire and vegetation dynamics, we used historical and modern satellite imagery (Corona KH-4b, Landsat-5,7,8, Resurs-P, SPOT-6,7). We performed comparative analysis of vegetation using high-resolution satellite data from different years.

The growing season length increased by 20 days and the mean temperature of the growing season increased by 1°C making climatic conditions suitable for trees. We showed that ca 40% of the total study area experienced fires at least once during the last 60 years. Within this period, shift from dry tundra to tree-dominated vegetation occurred in 6-15% of the area in the non-disturbed sites compared to 40-85% of the area in the burned sites.

How to cite: Ezhova, E., Sizov, O., Tsymbarovich, P., Soromotin, A., Prihod'ko, N., Petäjä, T., Zilitinkevich, S., Kulmala, M., Bäck, J., and Köster, K.: The role of fires for tundra-forest transition in northwest Siberia, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-11428, https://doi.org/10.5194/egusphere-egu21-11428, 2021.

The impact of temperate forests on climate still has open questions about their quantitative effect on radiative and thermal properties of the territory. The study addresses some of these questions and the analysis is based on the data from the Land-Use Model Intercomparison Project (LUMIP), which is the part of Coupled Model Intercomparison Project Phase 6 (CMIP6). The main aim of CMIP is to study climate on different periods of time from the past to the future with help of observations and Earth System Models (ESM).

LUMIP belongs to historical experiments and implies gradual deforestation with linear trend up to 1% all over the world during 50 years in pre-industrial period (1850-1899) and next 30 years with no change in forest cover. The goal of this experiment is to reveal the contribution of forest cover reduction on climate characteristics under quasi-constant anthropogenic forcing. This experiment was based on ESM simulations and the dataset of 8 ESM was retrieved for calculations of different climatic characteristics for the territory of Ukraine. These models have different spatial resolution, the initial and the final forest cover in grid cells respectively. Therefore, we analysed ESMs one-by-one and summarised the results over latitudinal zones. To analyse radiative regime we used monthly data of downwelling and upwelling shortwave radiation, which affect thermal regime estimated via surface and 2-m air temperature changes as well as mean daily and annual ranges. Anomalies of each characteristics were obtained over the base averages of the first 20 years of deforestation (1850-1869), which were further smoothed using the 5-year running mean.

It is known that the forest cover influences the ratio of surface downwelling and upwelling shortwave radiation, particularly, via albedo. We found the highest changes in albedo in winter season, most probably due to the presence of snow cover. Increase of albedo is well correlated with deforestation and the maximal rate of 18%/50 years was found in the Carpathians in winter. There were much less changes in warm season with rates up to 2%/50 years due to small difference between values of forest (~3-10%) with grass (~10-30%) than snow albedo (~40-90%).

These changes in radiative properties cause shifts in temperature regime with moderate and strong negative correlations between albedo and both surface and air temperatures. Higher albedo in winter season caused the decrease of mean monthly surface temperature up to -0.4℃/10 years in winter and -0.3℃/10 years in warm season. Values of changes of mean monthly air temperature corresponded to surface temperature changes and they were -0.4℃/10 years in winter and -0.2℃/10 years in warm season. Based on mean maximum and minimum monthly temperatures we found that deforestation also affected mean daily air temperature range only in winter with tendency up to 0.1–0.3℃/ 10 years. Meanwhile the models showed controversial results for annual air temperature range. One of the essential research outcomes we found that the impact of gradual deforestation on the thermal regime was shifted on approximately 20 years and diminished after stopping land cover change.

How to cite: Pysarenko, L. and Krakovska, S.: Impact of deforestation on surface radiative properties and temperature characteristics in Ukraine based on LUMIP CMIP6 datasets, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-7726, https://doi.org/10.5194/egusphere-egu21-7726, 2021.

Investigations of active soil layer on the Research station “Ice Base Cape Baranova’’ had been started in February 2016 after installation on the meteorological site sensors of Finnish Meteorological Institute: thermochain with IKES PT00 temperature sensors at depths of 20, 40, 60, 80 and 100 cm, soil heat flux sensor HFP, and two ThetaProbe type ML3 soil moisture sensors. Based on the results of measurements annual cycle of soil temperature changes was revealed with amplitudes 10 - 15 ° C less than the amplitudes of surface air layer temperature (Ta) and especially the temperature of the soil upper surface (Tsrad), in great degree determined by short-wave radiation heating and long-wave radiation cooling. Approximation by linear fittings shows average rates of increase Ta - 0.4°C/year, Тsrad - 0.3°C/year, and temperatures of active soil layer - 0.2°C/year.

The data on thermal regime of active soil layer and characteristics of energy exchange in atmospheric surface layer make it possible to draw the conclusion about the reason for the abnormally warm state of the upper meter soil layer in summer 2020, despite in March during the whole period under study active soil layer was the warmest in 2017. Comparison in temperatures of the underlying surface and characteristics of surface heat balance during period under study showed that in 2020 the temperature of the soil surface at the end of May for a short time reached the temperature of snow melting. It is happened 25 days earlier than in 2017 as well as other years and led to radical decrease in surface albedo, sharp increase of heat flux to the underlying surface, and increased duration of active soil layer heating.

Additionally, permafrost thawing studies using a manual contact method were carried out on the special site, organized according to CALM standards. These studies showed significant variety of soil active layer thicknesses in the relatively small area (~0.12 km²), which indicates significant spatial variability of microrelief, structure and thermophysical properties of soil, as well as vegetation, typical for Arctic desert. Calculations carried out with version of the well-known thermodynamic Leibenzon model for various parameterizations of vegetation and soil properties partly described peculiarities of spatial variability of observed thawing depths.

How to cite: Makshtas, A., Bogorodski, P., and Jozhikov, I.: Thermal regime of soil active layer at the Bolshevik Island (Archipelago Severnaya Zemlya) during 2016 – 2020 years, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-8838, https://doi.org/10.5194/egusphere-egu21-8838, 2021.

Yamal Peninsula is one of the significant region which terrestrial and aquatic landscapes are sensitive to the climate change. Geochemical processes in lakes can show impact of climate variability on hydrochemical and biological specific, trophic and ecological status. During 2012-2013 and 2018-2020 several Yamal lakes were observed during the summer field investigations. Water samples and sediment cores were taken and analyzed. Distribution of hydrochemical data is wide and cover Yamal coastal zone and central part of the peninsula including several anthropogenic chanced ecosystems. Sediment cores were taken in river terraces of Yuribey, Erkuta, Pysedeiyakha rivers, marine terraces of central Yamal (Neitinskie Lakes), and small core from Beliy island (North part of Yamal). Main ions and trace elements in lakes will be presented in a report as well as TOC/TC, grain-size, dating and paleoecological description of sediments. In order to reconstruct recent environmental and ecological changes half-core MSCL logging (physical properties, 0.5 cm spacing) and half-core XRF scanning (chemical composition, 0.1 cm spacing) have been applied for cores from Neitinskie Lakes (central part of Yamal). The first results of scanning and the statistic will be presented in the report. Comparison of aquatic ecosystem geochemistry for different parts of Yamal peninsula allow to explain the climate impact in different landscapes. Studies supported by RFBR 18-05-60291.  MSCL logging and XRF scanning have been done in Shirshov Institute of Oceanology of RAS by Geotek MSCL-XYZ instrument using.

How to cite: Fedorova, I., Zdorovennov, R., Kadutskiy, V., Fedorov, G., Shestakova, E., Zdorovennova, G., Guzeva, A., Chernyshova, M., Chetverova, A., Frolova, L., and Nigamatzyanova, G.: Geochemical sensitivity of lacustrine ecosystems of Yamal Peninsula (Russian Arctic) to climate change, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-15069, https://doi.org/10.5194/egusphere-egu21-15069, 2021.

Decadal changes in sea-ice thickness are one of the most visible signs of climate variability and change. To gain a comprehensive understanding of mechanisms involved, long time series, preferably with good uncertainty estimates, are needed. Importantly, the development of accurate predictions of sea ice in the Arctic requires good observational products. To assist this, a new sea-ice thickness product by ESA Climate Change Initiative (CCI) is compared to a set of five ocean reanalysis (ECCO-V4r4, GLORYS12V1, ORAS5 and PIOMAS).

The CCI product is based on two satellite altimetry missions, CryoSat-2 and ENVISAT, which are combined to the longest continuous satellite altimetry time series of Arctic-wide sea-ice thickness, 2002–2017. The CCI product performs well in the validation of the reanalyses: overall root-mean-square difference (RMSD) between monthly sea-ice thickness from CCI and the reanalyses ranges from 0.4–1.2 m. The differences are a sum of reanalysis biases, such as incorrect physics or forcing, as well as uncertainties in satellite altimetry, such as the snow climatology used in the thickness retrieval.

The CCI and reanalysis basin-scale sea-ice volumes have a good match in terms of year-to-year variability and long-term trends but rather different monthly mean climatologies. These findings provide a rationale to construct a multi-decadal sea-ice volume time series for the Arctic Ocean and its sub-basins from 1990–2019 by adjusting the ocean reanalyses ensemble toward CCI observations. Such a time series, including its uncertainty estimate, provides new insights to the evolution of the Arctic sea-ice volume during the past 30 years.

How to cite: Uotila, P., Siponen, J., Rinne, E., and Tietsche, S.: A means-corrected estimate for the Arctic sea-ice volume in 1990–2019, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-3840, https://doi.org/10.5194/egusphere-egu21-3840, 2021.

Climate change in the Arctic is noticeable and affecting the well-being of the population. The health and emotional state, food and water availability, livelihoods are on the threat. The towns are particularly sensitive to climate change. Their population and infrastructure density is exceptionally high, and temperature fluctuations, as well as extreme weather events, have an exceptionally strong impact on air and water quality, health and other components of human well-being. At the same time, urban communities in the Arctic, especially in industrial development zones, represent a little-studied area in this case.

The report presents the interdisciplinary study results concerning the climate change consequences for the population of Russian Arctic industrial developed areas. The study carried out in Murmansk Region which is a highly industrial and highly urbanized region that is completely included in the Arctic zone of the Russian Federation. Qualitative methods were used; in-depth (more than 50 questions) interviews were conducted with residents of several towns in the region. The study showed corresponds between the subjective perceptions of climate change by urban residents of the Murmansk Region with objective data on meteorological parameters changes. The surveyed urban residents feel changes in health and environmental management practices, and many respondents associate these changes with climate fluctuations. Such a phenomenon as the destruction of infrastructure (residential, public and industrial buildings, roads, energy infrastructure) due to climate change has not been identified. Concerns have been raised about the potential impact of climate warming on the ability to have a decent job due to reduced employment in some industries (such as energy).

The results obtained contribute to a better understanding of the social consequences of climate change in the Russian Arctic. This is important for adaptation actions development.

How to cite: Klyuchnikova, E., Riabova, L., and Masloboev, V.: Social consequences of climate change in the Arctic towns, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-9669, https://doi.org/10.5194/egusphere-egu21-9669, 2021.

A recurring question among research projects is how to optimize the use data that already exists and to identify its stakeholder’s needs, particularly in effort to bring services to a wider community outside academia. We propose a hackathon to allow the collaboration between civil, educational, business and governmental actors to address environmental challenges with the use of environment scientific data from international projects.

Hack the Arctic is co-organized by the Institute for Atmospheric and Earth System Research (INAR)/University of Helsinki, the Integrated Carbon Observation System Research Infrastructure (ICOS-ERIC) Headoffice, and the Environmental Research Infrastructures (ENVRI) Community. The hackathon event aims to enhance the usage and impact of environmental research data by and for society. The 48 hr event will gather multi-disciplinary teams through a public call to make use of existing environmental data from a network of research projects to develop services addressing the needs of different end-users. The participating teams will be mentored by researchers and data scientist in the use of the data. A panel of judges comprising of science mentors, innovation specialists and government sector actors will assess the implementation of the final pilot products at the end of the event.

We present Hack the Arctic as an up-and-coming alternative to expand the usage and visibility of research data and to make it widely accessible to a broader (nonacademic) audience by offering mentorship from data and scientific experts under one roof.

How to cite: Buenrostro Mazon, S., Brus, M., Ahlgren, K., Mahura, A., Lappalainen, H. K., and Kulmala, M.: Hack the Arctic: transforming data into solutions as a community , EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-14631, https://doi.org/10.5194/egusphere-egu21-14631, 2021.

MODEST (Modernization of Doctoral Education in Science and Improvement Teaching Methodologies) is a capacity building project funded by the Erasmus+ programme.

The project is coordinated by the University of Latvia. There are three other EU partners (from Finland, Poland and the United Kingdom) and a total of ten partners from three partner countries (Russia, Belarus and Armenia).

The project aims to improve the structure and content of doctoral education and the internal capacities of services that manage doctoral studies in accordance with the modern European practices, to facilitate a successful adherence with Bologna process reforms and its instruments, to improve and increase the quality of international and national mobility of doctoral students of Armenia, Belarus and Russia, and to establish a sustainable professional network providing the use of participatory approaches and ICT-based methodologies.

During the past year, almost one hundred members of academic and administrative personnel as well as doctoral students have contributed to creating a total of 14 new courses mainly in transferable skills: Research methodology and research design; Project writing, project management, and funding sources; International research writing and presentation skills; Research ethics, Intellectual property rights and personal data protection; 3I - Interdisciplinarity, interculturality, internationalization in research; Organization of doctoral training; Educational/constructive alignment, design and implementation of courses for doctoral studies; Digital literacy; Data analysis and expert systems; Virtual environment; Commercialization of research, managerial skills; Personal development; Complexity; and Sustainable development and global challenges of 21st century. Each course has specific target group(s) such as PhD students, university teachers, doctoral programme managers, or administrative staff.

Summary of each developed course – aims, learning outcomes, content (including course blocks on lectures, seminars, homeworks, etc.), planned learning activities and teaching methods, assessment methods and criteria, and other relevant – will be presented. The developed courses will be an integral part of the Doctoral Training Centers for PhD students to be established in the MODEST partner universities in Armenia, Belarus and Russia.

The MODEST project serves as a great example of transfer of good practices in higher education, especially on doctoral level, but it has also created new connections for educational and scientific collaboration. From the PEEX perspective, MODEST is an important initiative strengthening connections between European universities and institutions in Russia, Belarus and Armenia. The project will continue until 2022. More detailed information is available at www.emodest.eu.

How to cite: Lauri, K. A., Mahura, A., Karppinen, S., Obukhova, I., Kalganova, T., Frankowicz, M., and Skendere, I.: Science education for doctoral students: MODEST approach and experience, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-12840, https://doi.org/10.5194/egusphere-egu21-12840, 2021.