Category Archives: Atmosphere

Building ICOS RI: Integrated Carbon Observation System Research Infrastructure

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logotransparent ICOSThe perturbed global biogeochemical cycles of the greenhouse gases are a major driving force of current and future climate change. The IPCC has concluded that a large part of the observed rise of global temperature is very likely due to increasing greenhouse gases in the atmosphere, driven by man-made emissions overtaking the natural cycles of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). Deeper understanding of the driving forces of climate change requires full quantification of the greenhouse gas emissions and sinks and their evolution. The mission of ICOS RI is to enable research to understand the greenhouse gas budgets and perturbations. ICOS RI will

  • track carbon fluxes in Europe and adjacent regions by monitoring the ecosystems, the atmosphere and the oceans through integrated networks,
  • provide the long-term observations required to understand the present state and predict future behavior of the global carbon cycle and greenhouse gas emissions,
  • monitor and assess the effectiveness of carbon sequestration and/or greenhouse gases emission reduction activities on global atmospheric composition levels, including attribution of sources and sinks by region and sector.

Leading the negotiations to establish the European ICOS organization has been one of the major efforts of the division, together with the FMI, for the last couple of years. At the same time the Finnish national station network to monitor the greenhouse gas has been upgraded and built to match the ICOS standards. ICOS is currently in the transitional phase between the preparatory phase project and ICOS ERIC (European Research Infrastructure Consortium). The leader of the transitional phase is prof Timo Vesala. ICOS Director General recruitment process is going on and the new DG should start in the Head Office by the end of this year.

The structure of ICOS RI consists of the following parts:

  • Organized ICOS National Networks (such as ICOS-Finland, http://www.icos-infrastructure.fi)
  • ICOS Central Facilities (including Atmospheric Thematic Centre, Ecosystem Thematic Centre, Ocean Thematic Centre, Central Analytical Laboratory),
  • Its European legal entity, ICOS ERIC, including the Head Office and Carbon Portal. ICOS ERIC is the European legal entity to manage the activities of ICOS RI. ICOS ERIC is responsible for coordination, management, scientific, strategic and technical planning, and outreach of ICOS RI.

The Head Office of the ICOS ERIC legal entity and coordination of the ICOS RI is in Helsinki, Finland.

ICOS ERIC application has been submitted by the Finland’s permanent representation to the EU to the European Commission for step 1 evaluation in 21.6.2013. The EC will assess the application to ensure its compliance with the requirements of the ERIC Regulation. Four to five independent experts will assist the Commission in its assessment of the application’s compliance regarding the necessity, added value, access, mobility, knowledge transfer and dissemination of the RI. The next step will commence in autumn and include the signature process between the member and observer countries. ICOS ERIC is planned to be established early 2014.

Kuvankaappaus 2013-6-26 kello 12.15.01More information at: http://icos-infrastructure-transition.eu

Marjut Kaukolehto

Atmospheric supermodels

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Kuvankaappaus 2013-6-25 kello 14.29.36When the calendar reads June and the Scandinavian countries register the warmest temperatures in Europe, the most intuitive idea is not to stay indoors, draw down the curtains and start coding. However, that was exactly what 18 students and assistants did when the first summer school on atmospheric modelling took place in the modern building of Ingvar Kamprad Design Centre, Lund University, Lund, Sweden.

The school consisted of lectures on atmospheric sciences and computational modelling. During the course the participants were creating their own one-dimensional column model of atmospheric boundary layer. The coding language was Fortran 90 as is the tradition in atmospheric science and many other sciences. The students described the boundary layer meteorology by including the equations of flow and a first order turbulence closure. Emissions of volatile organic compounds from the vegetation were then added. Relevant atmospheric chemical reactions were likewise included and the chemical kinetics was modelled by numerically solving systems of differential equations. Lastly, the students coded nucleation, coagulation and condensation of aerosol particles and coupled the concentrations of the chemical compounds and the aerosol particles to the meteorological mixing.

The course was held from the 10th to the 19th of June and was organised by University of Helsinki and Lund University and funded by the Nordic Master’s Degree Programme in Atmosphere-Biosphere Studies (ABS) and Cryosphere-Atmosphere Interactions in a Changing Arctic Climate (CRAICC). We had participants from 5 universities and institutions and 10 different countries. The list of teachers included: from Lund University: Pontus Roldin and from University of Helsinki: Michael Boy, Sampo Smolander, Luxi Zhou, KV, Henri Vuollekoski and Ditte Mogensen.

Ditte Mogensen

OpenIFS – a leading model of atmospheric dynamics

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Dr Sinclair (right) at the OpenIFS meeting.

Dr Sinclair (right) at the OpenIFS meeting.

Professor Heikki Järvinen and researcher Victoria Sinclair use the numerical weather forecast model OpenIFS, recently released by the European Centre for Medium-Range Weather Forecasts (ECMWF), in their teaching and research.  OpenIFS is an open version of the IFS system currently in use at ECMWF for operational weather forecasting.  IFS is the leading model in its field: it has excellent forecasting ability for more than 6 days on average (measured by an 80% anomaly correlation limit) and was able to predict the track of superstorm Sandy as many as 7.5 days before the storm struck New York. The main competitors of the IFS are the Met Office and NCAR numerical forecast models.

In early June, Prof Järvinen and Dr Sinclair organised a 3-day workshop at the University of Helsinki for users to discuss OpenIFS model and its future prospects. Hands-on tutorials were organized with help of ECMWF staff at the computer rooms of the Physicum. All participants ran the model at the CSC’s CRAY supercomputer and analysed the results with the Metview visualization tools.

Prof Järvinen is a happy user of OpenIFS: “We are one of the first universities to have a licence for OpenIFS. With the OpenIFS, we can study questions about atmospheric dynamics that are both relevant and inspiring for the students. OpenIFS represents top-end science and there is potential for societal impact though its operational use. In our division, we have strong expertise in GHG, aerosols, and atmospheric processes, but OpenIFS also gives an opportunity to study marine aspects, which is on our agenda as well. In addition, by educating our students to use and understand numerical weather forecast models, we provide them job-relevant skills which can be easily applied to the use of Earth system models.”

The Division of Atmospheric Sciences has a commitment to develop a cutting-edge numerical meteorology laboratory course, and OpenIFS is an ideal tool for that. “I think OpenIFS is right for us and provides rich opportunities. It is relatively easy to use and it has a multitude of research applications. It is modern, modular, well documented, and computationally extremely efficient. There are also excellent training opportunities at ECMWF and within the OpenIFS community”, says professor Järvinen.

Victoria Sinclair’s initial experience of using OpenIFS for research has been positive. “I started working with OpenIFS in January and all went well from the start; my aim was to use it to understand how weather systems transport moisture to the interior of Antarctica by means of case studies, sensitivity experiments, and by analysing large-scale dynamics. I also wanted to calculate moisture budgets and to use the model in teaching synoptic meteorology”, Victoria says. “I think OpenIFS is a very good tool for a teacher to explain how weather systems work.”

Victoria found OpenIFS practical and easy to use. “IFS is a state-of-the-art numerical weather prediction model and well known internationally. It is computationally efficient, and as a global model, there are no difficult lateral boundary conditions. One simulation may have more than one use; furthermore, I can study both polar regions at once. IFS is well tested and well documented; as a European model, it is also more acceptable for some European funding agencies than American models.”

What about weak points? “Well, there are relatively few academic users at the moment, and this limits the sources of help and advice. If I have a problem with something, it is unlikely that someone else has ended up in the same situation before outside ECMWF. Also, the output is not that user friendly. I changed from IFS’s plotting programme, Metview to Matlab at some point, although Metview definitely has lots of potential. I just need to invest some time to learn how to use it.“

In summary, Prof Järvinen and Dr Sinclair think that OpenIFS is a very promising project for researchers, and for teaching, but that there is still quite a lot of room for improvement, especially in terms of user-friedliness.Prof Järvinen (left) at the OpenIFS meeting.

Tanja Suni, Heikki Järvinen, Victoria Sinclair

More information about ECMWF, IFS, and OpenIFS

http://www.ecmwf.int/
http://www.ecmwf.int/research/ifs/
https://software.ecmwf.int/wiki/display/OIFS/OpenIFS+Home

Latest views on global CO2 emissions and sinks

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Kuvankaappaus 2013-6-14 kello 14.12.41During the first week of June, the 9th International Carbon Dioxide Conference held in Beijing gathered together the carbon community from different parts of the world. Conference presentations ranged from climate policy to in-situ and remote observations of CO2 and modelling of CO2 emissions and sinks.  As one might expect, many of the presentations considered anthropogenic CO2 emissions. Alarming news was that during recent years, global CO2 emissions have followed the worst scenarios predicted by different sources; the hope that the emissions would follow lower estimates is declining. Besides the growth in emissions, one of the biggest questions among the community seemed to be the strength of carbon sinks on land surface and in the ocean.  Currently, oceans are considered to store about 1/3 of anthropogenic CO2 emissions but this number includes large uncertainties. Furthermore, several presentations referred to modelling studies suggesting that the carbon sink to oceans is actually smaller than previously expected, and that the sink may saturate more rapidly.

That China was the host of the conference seemed apt: between 1990 and 2011, the contribution of China’s CO2 emissions on a global level increased from below 10% to 26%.  In 1978, less than 17% of the Chinese population lived in cities, whereas currently this fraction is already above 50%. Urbanization, industrialization, and globalization are considered to be the main CO2 emission growth drivers. Despite the enormous increase in emissions, some regions in China, such as Beijing, have been able to keep their emissions fairly steady for the last ten years. Moreover, looking at CO2 emissions per capita, USA and EU are still ahead of China.

The conference finished in the conclusion that clearly more work in understanding the sinks and emissions of CO2 is necessary, particularly regarding the role of soil and water. For more information, please see the special issue in Tellus B (Vol. 62, Issue 5).

Leena Järvi

Finnish participants

Leena Järvi and Timo Vesala, Division of Atmospheric Sciences, Department of Physics, UHEL

Anne Ojala and Pekka Kauppi, Department of Environmental Sciences, UHEL

 

Climate and air quality research onboard a zeppelin

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16052013608Since the beginning of May 2013, a zeppelin has been flying over southern Finland. The zeppelin was brought to Finland as part of a European project PEGASOS to measure aerosol particles and trace gases in the lowest layers of atmosphere up to about 1.5 km.

As part of PEGASOS (Pan-European Gas-AeroSOls-climate interactions Study), an international group of scientists studies the effect of human emissions to climate change. Last summer research flights with the zeppelin were carried out in polluted areas in Central and Southern Europe. This time, we measure in Finland where the air is cleaner, anthropogenic emissions smaller, and biogenic effects more important.

In Finland 30 scientists, 10 technicians and 2 pilots operate the zeppelin and the instruments it is carrying. While in Finland, the zeppelin is stationed at Jämijärvi airport and the flights are mostly directed between Jämijärvi and Hyytiälä or around Jämijärvi.

The “flying laboratory” build in the zeppelin is equipped with state-of-art scientific instruments specially designed to investigate aerosol particles and trace gases. The instruments are divided into three cabin layouts and only one can fly at a time. Each of the layouts has a specific scientific focus point: new particle formation, photochemistry, and secondary organic aerosol – together covering a wide range of atmospheric physics and chemistry.

The zeppelin complements the extensive ground-based measurements and airplane measurements carried out in the planetary boundary layer. This airship offers a unique combination of capabilities which is not available when employing other aircrafts. The airship can stay at nearly fixed position, making it possible to follow time development of various events, such as industrial emissions or particles from natural sources. On the other hand, the airship can change height quickly and operate also at low altitudes which allows for measurement of the vertical profiles of trace compounds with high time resolution, also at the lowest hundreds meter above ground.

The research flights will continue until mid-June 2013. So far, the measurements have given new information about atmospheric mixing and layering as well as transportation of particles and gases in the atmosphere and detailed information on spatial variation of fine particles and gases from natural and human made sources.

Hanna Manninen & Taina Yli-Juuti

Blog for the EU PEGASOS Project:
http://eu-pegasos.blogspot.fi/

PEGASOS Project home page:
http://pegasos.iceht.forth.gr/

 

Measuring smaller and smaller particles

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Katrianne Lehtipalo working with the Particle Magnifier in Hyytiälä.

Just a few years ago, there were no instruments which could detect recently formed atmospheric clusters, or the particle precursor vapours at atmospheric concentration levels. We needed to make those instruments ourselves. The largely unstudied size range at 1-3 nm is an area which calls for both scientific discoveries and technical innovations.

Airmodus is a spin-off company from the University of Helsinki, Division of Atmospheric Sciences. It was started in 2010 in order to commercialize some of the innovations that were needed for studying new particle formation.  Our flagship product is the Particle Size Magnifier, which is still the only commercially available particle counter detecting particles as small as 1 nm.

During the currently on-going PEGASOS campaign, there are Particle Size Magnifiers both at the ground station SMEAR II in Hyytiälä and up in the air carried by a Cessna airplane and the Pegasos zeppelin. This is the first time when airborne measurements start from 1 nm, so expectations from the results are high.

Katrianne Lehtipalo
Science Manager
Airmodus

Sulphur deposition causes a large‐scale growth decline in boreal forests in Eurasia

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Map of sulphur depositions for the study sites in 1980. Adopted from Savva & Berninger (2010).

Human activity has altered climate, atmospheric carbon dioxide concentrations, and the concentrations of several pollutants over the last few decades. At the same time, short‐term reactions of tree growth to climatic variations have changed during the last few decades, for reasons that are poorly understood. However, the effects of the pollutants on growth of boreal forests in these remote areas have not been quantified, but even small changes in the productivity of boreal forest should have a large effect on the carbon balance.

The growth of Scots pine, the most important forest species in boreal Eurasia, has declined by about 17% or 0.0025 mm per year from the 1930s to the 1980s in northern Eurasia. We determined this by analysing 40 tree ring chronologies north of 60°N latitude and and factoring out the age and climate effects. Although the study sites were previously considered low‐pollution pristine environments, the growth decrease was significantly related to sulphur depositions. Additionally, we observed that the sulphur depositions rendered the Scots pine forests more sensitive to drought. Although the negative effects of local pollution on plant growth have been widely observed in the past, the long-term effects of sulphur emissions and its spread to ecosystems distant from the sources of pollution have never been previously documented at such a large scale.

These results are of fundamental importance for attempts to preserve the functioning of these forest ecosystems: sulphur deposition rates are still increasing in several regions of the world including the forested boreal areas of north-eastern China and eastern Russia. On the other hand, according to the European Monitoring and Evaluation Programme (EMEP) model, sulphur deposition at 35 sites in boreal Eurasia has been decreasing with a rate ranging from 0.25 to 2.92 kg S ha-1 per every 5 years over the period 1980 to 2000. This decrease in sulphur deposition should slow down the growth decline in boreal Eurasia, but the rate of growth decline will depend upon the ability of trees to recover from sulphur deposition effects, and combination of other environmental factors, such as the frequency of droughts.

Yulia Savva* and Frank Berninger*°

*Departement des Sciences Biologiques, Université du Québec à Montréal, Montreal, Quebec, Canada
°Department of Forest Ecology, University of Helsinki

Savva, Y., and F. Berninger (2010), Sulphur deposition causes a large‐scale growth decline in boreal forests in Eurasia, Global Biogeochemical Cycles 24, GB3002, doi:10.1029/2009GB003749.

 

 

 

Land-atmosphere interactions in urban environment

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Today, more than half of world’s population resides in urban areas, and this fraction is

View off the roof top of Dynamicum showing the SMEAR III measuring tower. Photo: Antti-Jussi Kieloaho.

further expected to increase rapidly in the next decades. Thus, a growing number of people will be affected by urban climate. The ability to understand the processes leading to this specific micro-climate is crucial for sustainable urban planning and our quality of life.

In our Centre of Excellence, the Micrometeorology group has been observing the interactions between urban surface and the above atmosphere at the urban measurement station SMEAR III (Station for Measuring Ecosystem Atmosphere Relations) since 2005. We measure the vertical exchange of energy, water, carbon dioxide and aerosol particles with the state-of-the-art methodology, the eddy covariance technique, at two locations:  on a measurement mast in semi-urban Kumpula and in downtown Helsinki on top of Hotel Torni.  In addition to these continuous measurements, our group also conducts short-term campaigns to observe the land-atmosphere exchange of N2O and volatile organic compounds (VOC) in this urban micro-climate.

The aim of these measurements is to collect long time series of simultaneously measured exchange processes to develop parameterizations for various atmospheric models, and to understand the processes and their changes in time. We are interested how the different urban land use types, particularly green areas, affect the vertical exchange of different variables. For example, as a rough estimate for carbon dioxide, Annika Nordbo, Leena Järvi, Sami Haapanala, Curtis Wood and Timo Vesala recently found that if natural areas cover over 80% of the urban surface, the uptake of vegetation exceeds the carbon dioxide emissions in the source area (Nordbo et al. 2012). Thus, our measurements provide information for urban planners as well as evaluation data for air quality, numerical weather forecast and climate models.

The measurements are also part of the new Urban Boundary-layer Atmosphere Network (UrBAN) which combines a variety of different instrumentation providing data of the interaction between an urban surface and the atmosphere at different spatial scales. The network is a joint effort by the Finnish Meteorological Institute and the Division of Atmospheric Sciences. We also collaborate with groups around the world working with urban flux measurements. The near future plan is to compare the turbulent energy balance fluxes from Beijing and Helsinki using both measurements and modelling approaches.

Webpages:
http://www.atm.helsinki.fi/SMEAR/index.php/smear-iii
http://urban.fmi.fi

Reference
A. Nordbo, L. Järvi, S. Haapanala, C.R. Wood and T. Vesala (2012b). Fraction of natural area as main predictor of net CO2 emissions from cities. Geophys. Res. Lett., 39, L20802, doi: 10.1029/2012GL053087

Are diesel engines the answer in mitigating traffic emissions?

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Photo: Antti Mannermaa in Tekniikka & Talous

Diesel engines are amongst the largest emission sources in urban air. The emissions consist of soot particles of about 40-80 nm in diameter. The engines emit also nanoparticles at less than 20 nm or so in diameter, consisting of various hydrocarbons and possibly also sulphur (in case of sulphur-containing fuel).

Why is it so attractive to switch to diesel instead of a less emitting gasoline engine? The answer is in fuel economy. In Finland, the national policy towards the diesel fleet has changed over the last couple of years. Today the price per liter is almost equal for both diesel and E10 gasoline. The owner of the diesel car needs to pay a monthly tax, and the savings must come from the more economical engine.

The emissions of diesel engines are rather well know and there is a continuous effort to limit the emissions even more. In 2013, the new EURO VI limits for heavy-duty vehicles will be 0.01 g/kWh for PM (particulate matter) and 0.4 g/kWh for NOx. If you compare these to the EURO I values just 20 years ago the change is dramatic: EURO I for PM was 0.36 g/kWh and for NOx 8 g/kWh. Unfortunately, the diesel engines tend to be strong and last forever, so we have to wait for a while until the fleet has majority of EURO VI level engines.

In order to cut down the emissions to EURO VI level, changes in engine technology alone will not be sufficient. This emphasises the importance of the after-treatment of the exhaust gases. Several different types of catalysts and filters exist. How well do these work? What is their efficiency? Answering these questions requires intensive research.

What makes the development towards lower emissions even more challenging is the need to consider also the effects of new type of fuels. It is possible to produce diesel fuel from biomass-based renewable energy sources, and research towards this goal is already going on. These new-generation fuels aim for a lower CO2 footprint.

I am acting as an opponent for a recent PhD thesis from Tampere Technical University that has focused on all of these aspects in a wide set of experiments. The overall message of the thesis is clear: with new technology, one can fight against particle and gaseous emissions successfully together with lower greenhouse gas emissions.

By Prof Kaarle Hämeri (aerosol physics, Division of Atmospheric Sciences)

See original blog post at http://hameri.blogspot.fi. The link for the press release of the thesis work can be found here in Finnish.

Mind-mapping nitrogen cycling in boreal forests

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Mind-map of nitrogen cycling in boreal forests by the N group and collaborators: Dynamic nitrogen (N) pools processes in a boreal forest. Arrows stand for processes between the pools, red dots mark unknowns in the N cycle, and green dashed lines name ongoing or coming projects to solve some of the questions.

Reactive nitrogen (N) has a key role in the atmospheric chemistry and functioning of boreal forests. After years of studying the complex interactions of N cycling in boreal forests, Janne Korhonen et al. (2012) have calculated the N balance of the Hyytiälä SMEAR II Scots pine forest. The study shows that the forest ecosystem is a very efficient N recycler. Based on the new results, the atmospheric N deposition is much higher than previously estimated, and dry and wet organic deposition are important components of the total N input. However, although the pools, annual inputs, outputs and overall N cycling in the boreal forest have been resolved, new questions arise of the short-term dynamic N processes (such as amine formation via decomposition of soil organic nitrogen). These processes are important for the atmospheric chemistry and connect N even to climate effects of aerosols.

The N group at the Division of Atmospheric Sciences (Janne Korhonen, Antti-Jussi Kieloaho, and supervisors Mari Pihlatie and Jukka Pumpanen) are applying and developing new methods together with chemists, physicists and microbiologists. Current projects linking N and the atmosphere include studies on amine concentrations and fluxes, and the effect of fresh carbon input on soil organic nitrogen turnover (NITRGOFUNGI). In the future, our main focus in the nitrogen research will be to estimate reactive N emissions from soil and canopy, N transformations, and the fate of N deposited on to the forest canopy.

Contributors to the mind-map (working in the Division’s nitrogen group):

  • Jussi Heinonsalo (microbiology)
  • Maarit Raivonen (forest ecology)
  • Johanna Joensuu (forest ecology)
  • Timo Vesala (professor, micrometeorology)
  • Jukka Pumpanen (soil ecology)