Statistics, climate research and applications

International Convention Center, Jeju

Between 24th and 28th June, an international meeting on statistical climatology (IMSC) was held in Jeju Island, Republic of Korea. The meeting is one of the largest in the field and is held every third year. Well over 200 researchers participated, including three from the Division of Atmospheric Sciences. The research field itself is very wide, covering several climate research topics which involve the use of statistical methods and their application to (often) large/complicated datasets used in climate research. As a general description, “The aim of IMSC is to promote good statistical practice in the atmospheric and climate sciences and to maintain and enhance the lines of communication between the atmospheric and statistical science communities.”

The Earth’s climate system is very complicated, involving myriads of processes many of which are poorly known. However, climate research is not only about to understand the underlying processes. The analysis of existing data also has several issues related to it, involving related expertise and experience. This is emphasized by the ever-growing amount of geodata, comprising both observations and model simulations. Nowadays, it has become common for research projects to freely distribute the produced data for all interested users who then can exploit it for their personal research purposes. In this way, the data developers can also get more feedback from the data users and the outcome eventually has benefits to both parties. Indeed, research methods used in natural sciences are fundamentally more data-oriented today than a few decades ago. While progress in science also requires production of new data, for many applications there already exists a wealth of data which is far from being comprehensively analyzed.

As climate in any specific place can eventually be described as averaged weather, the conventional variables familiar from everyday weather forecasts (whether observed or modelled: surface temperature, precipitation, wind speed, humidity, …) have also a very important role in climate research and in any applications related to it. This is emphasized by the fact that these surface variables are the most meaningful for most of the climate data users, in their own right and as an input for impact studies. Some of the most important questions to ask by anyone planning to apply any adaptive measures in order to prepare for changing climatic conditions are:

“How much is it likely for temperature and precipitation to change at my location during the 21st century?” “What will happen to precipitation intensity in the future?” “How sensitive is my crop to droughts and will their frequency increase?” “How will river discharges change and what are the related uncertainty intervals?” “How important it actually is to get the future climate simulations right for my application?” Indeed, societal interface is very close to many of the applications in the field – many sectors are sensitive to climate and weather. Without the field of applied climatology, much of the precious scientific basic research about process understanding would not be translated at all for numerous societal applications. This happens through climate predictions done with global/regional climate models: the overarching aim in large parts of geoscientific research is to improve future climate predictions by studying the actual processes and eventually implementing them as a part of a climate model.

The simulations of climate models are distributed to the users by some means, which is far from being a straightforward copy-and-paste activity. Many of the problems have no simple answer, but still desperately need to be assessed as they have a large importance in climate prediction. An honest scientific interpretation of the future climate predictions requires understanding of relevant processes affecting climate in any specific place (defined possibly by the user), statistical knowledge, and multidisciplinary interest from the people working at the science-society-policy interface. All of this emphasizes the importance of diverse research environment and knowledge that can integrate and condense information into better products and simultaneously facilitate adaptive decisions of the end-users by offering decent decision-support advice and products for them.

We cannot just build our fancy climate models indefinitely, but we also have to use them in practice. The impact-related research on the division helps climate data users to apply climate predictions better for their problems and therefore eventually facilitate their adaptive decisions. The importance of climate services is evermore growing, emphasizing the need to develop good practices and guidance for interpreting and using climate data. Without this kind of research, the interface between the climate science community and actual decision makers will deteriorate. Whatever impacts will be caused by changing climate, estimating them also involves the use of climate models. As a science community, we need to have credible methods and tools to be able to serve users and the wider society.

One poster session was held on each day

Jussi S. Ylhäisi
Jouni Räisänen
Olle Räty

Climate research group

Building ICOS RI: Integrated Carbon Observation System Research Infrastructure

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,
  • 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:

Marjut Kaukolehto

Atmospheric supermodels

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

Brainstorming for an iLEAPS-ESA Biosphere-atmosphere-society index

Kuvankaappaus 2013-6-25 kello 14.38.11

For the past few years, iLEAPS has been brainstorming about a 3-dimensional parameter or index that would describe the state of the biosphere, the atmosphere, and societies. The idea would be to explore the trajectories of all these three variables but, more importantly, to try and find any possible covariance between any two or among all three variables that would shed light on dependencies and interactions among biospheric, atmospheric, and socioeconomic processes in the past and in near-real time.

During the past year, the European Space Agency (ESA) has expressed strong interest to be involved in the development of such an index. Satellite information would indeed be indispensable because satellites can give information about large regions that are too remote and unattainable for ground-based observations.  ESA and iLEAPS co-organised a first workshop on the index on 13 June 2013 at the Max-Planck Institute in Munich.

The speakers in the workshop included experts in satellite observations, land use and land cover changes, social structures and stratification, data analysis, and socioeconomic sciences. One of the main problems with such a multidisciplinary index is deciding what kind of socioeconomic variables and indices should or could be used and how they could be linked with environmental policy, international trade, and land-use decisions. On the natural science side, many practical satellite applications exist that can produce useful data for describing the states of the biosphere and the atmosphere. Satellites are particularly useful for separating different land use and land cover types from one another – land management is of course one of the most direct links between socioeconomic and biospheric/atmospheric processes. However, although one of the main advantages of remote sensing is that it can be used to observe remote regions where ground-based observations are not possible, even satellite data is limited in some regions. Furthermore, satellite data will always need to be strengthened with ground-based observations and this is where international infrastructures and networks such as FLUXNET, ICOS, ACTRIS, LIFEWATCH and others come in.

Tanja Suni and Ari Asmi

OpenIFS – a leading model of atmospheric dynamics

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

Latest views on global CO2 emissions and sinks

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

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:

PEGASOS Project home page:


The future of the Arctic

In September 2012, Arctic sea ice cover declined to a record low, over 3 million square kilometers below the long-term average for the month. Photo: IIASA Newsletter

IIASA researchers and Finnish policymakers and scientists met in May to outline a new research agenda addressing the challenges facing the Arctic region.

The seminar, jointly organized by IIASA, The Finnish Prime Minister’s Office, and the Academy of Finland, brought together stakeholders to share views, discuss and clarify the kind of Arctic research that is most needed to help guide the region through an uncertain future. Prof Markku Kulmala took part in the meeting, giving a Finnish view on climate change issues. Other speakers included Prof Pavel Kabat, Director of the International Institute for Applied Systems Analysis IIASA, Austria; Ambassador Hannu Halinen, Arctic Affairs at the Finnish Ministry for Foreign Affairs; Minister Counsellor, Deputy Head of Mission, Ulrik Tideström, Embassy of Sweden in Helsinki; Special Adviser Christine Daae Olseng, Coordinator for the Polar Research Programme, the Research Council of Norway; Senior Vice President and Chief Techology Officer Kari Knuutila, Outotec Oyj, Finland; Director Teija Tiilikainen, Finnish Institute of International Affairs, Finland; and Dr., Researcher Seija Tuulentie, Finnish Forest Research Institute.

“The meeting was an important step in establishing a real, efficient and useful dialogue between policy makers and scientists. Our Division is involved in many such efforts because we find it is in the best interest of society in every respect”, says Prof Kulmala.

Climate change has hit the Arctic region harder than any location on Earth. Over the last 30 years, the sea ice that covers the Arctic Ocean has declined by over 40% in summer, opening up new routes for shipping and making oil extraction and fishing more feasible in previously impassable waters. In the same time period, average temperatures have risen twice as fast in the Arctic as in lower latitudes. The resulting thawing of permafrost can undermine infrastructure, and the climate shifts may disrupt marine and terrestrial ecosystems, as well as the cultures that depend on them.

These changes open up new economic opportunities for resource extraction, shipping, and tourism in Arctic countries, but also pose many new questions about how to guide sustainable economic development and avoid environmental damage.

IIASA researchers focus on many issues relevant to the Arctic, including energy resources, air quality, and fisheries. The Institute also integrates scientific analyses into the assessment of policy options and future scenarios, a function that could be vital in the rapidly changing region, which is becoming ever more important on the global economic and geopolitical stage.

The meeting was webcast. For more information, visit the Academy of Finland Web site:

Tanja Suni
Adapted from IIASA Newsletter, Issue 14, June 2013

Measuring smaller and smaller particles

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

Fire in boreal forests

Fire in eastern Lapland. Photo: Jukka Pumpanen

Forest fires have been the dominant disturbance regimes in boreal forests since the last Ice Age. Fire is the primary process which organizes the physical and biological attributes of the boreal biome and influences energy flows and biogeochemical cycles, particularly the carbon and nitrogen cycle. Forest fire activity is expected to increase significantly with changing climate, acting as a catalyst to a wide range of ecosystem processes controlling carbon storage in boreal forests. We compared the initial recovery of carbon (C) and nitrogen (N) pools and dynamics following fire disturbance in Scots pine (Pinus sylvesteris) stands in the boreal forests of eastern Lapland (Värriö Strict Nature Reserve), Finland, by sampling soils and measuring soil respiration from sample plots established in a  chronosequence of different forest sites with 4 age classes, ranging from 2 years to 150 years after fire disturbance (2, 40, 60, 150 years after fire). The sites are situated north of the Arctic Circle, near to the northern timberline at an average of 300 m altitude.

Our preliminary results show that forest fire has a substantial effect on the C and N pool in the litter layer decaying forest top soil layer, but not in the humus layer and in mineral soil layers. Soil respiration and biomass development showed similar chronological response to the time since the forest fire indicating that substantial proportion of the respiration was originating from the very top of the soil.

Jukka Pumpanen and Frank Berninger
Department of Forest Ecology
University of Helsinki