IGBP Northern Eurasia Study: Prospectus for an Integrated Global Change Research Project

This report was prepared by scientists representing BAHC, IGAC, and GCTE. It is a prospectus for an integrated hydrological, atmospheric chemical, biogeochemical and ecological global change study in the tundra /boreal region of Northern Eurasia. The unifying theme of the IGBP Northern Eurasia Study is the terrestrial carbon cycle and its controlling factors. Its most important overall objective is to determine how these will alter under the rapidly changing environmental conditions. (Also available in Russian.

Review of existing information on the interrelations between soil and climate change. (ClimSoil). Final report

Carbon stock in EU soils – The soil carbon stocks in the EU27 are around 75 billion tonnes of carbon (C); of this stock around 50% is located in Sweden, Finland and the United Kingdom (because of the vast area of peatlands in these countries) and approximately 20% is in peatlands, mainly in countries in the northern part of Europe. The rest is in mineral soils, again the higher amount being in northern Europe. 2. Soils sink or source for CO2 in the EU – Both uptake of carbon dioxide (CO2) through photosynthesis and plant growth and loss of CO2 through decomposition of organic matter from terrestrial ecosystems are significant fluxes in Europe. Yet, the net terrestrial carbon fluxes are typically 5-10 times smaller relative to the emissions from use of fossil fuel of 4000 Mt CO2 per year. 3. Peat and organic soils - The largest emissions of CO2 from soils are resulting from land use change and especially drainage of organic soils and amount to 20-40 tonnes of CO2 per hectare per year. The most effective option to manage soil carbon in order to mitigate climate change is to preserve existing stocks in soils, and especially the large stocks in peat and other soils with a high content of organic matter. 4. Land use and soil carbon – Land use and land use change significantly affects soil carbon stocks. On average, soils in Europe are most likely to be accumulating carbon on a net basis with a sink for carbon in soils under grassland and forest (from 0 - 100 billion tonnes of carbon per year) and a smaller source for carbon from soils under arable land (from 10 - 40 billion tonnes of carbon per year). Soil carbon losses occur when grasslands, managed forest lands or native ecosystems are converted to croplands and vice versa carbon stocks increase, albeit it slower, following conversion of cropland. 5. Soil management and soil carbon – Soil management has a large impact on soil carbon. Measures directed towards effective management of soil carbon are available and identified, and many of these are feasible and relatively inexpensive to implement. Management for lower nitrogen (N) emissions and lower C emissions is a useful approach to prevent trade off and swapping of emissions between the greenhouse gases CO2, methane (CH4) and nitrous oxide (N2O). 6. Carbon sequestration – Even though effective in reducing or slowing the build up of CO2 in the atmosphere, soil carbon sequestration is surely no ‘golden bullet’ alone to fight climate change due to the limited magnitude of its effect and its potential reversibility; it could, nevertheless, play an important role in climate mitigation alongside other measures, especially because of its immediate availability and relative low cost for 'buying' us time. 7. Effects of climate change on soil carbon pools – Climate change is expected to have an impact on soil carbon in the longer term, but far less an impact than does land use change, land use and land management. We have not found strong and clear evidence for either overall and combined positive of negative impact of climate change (atmospheric CO2, temperature, precipitation) on soil carbon stocks. Due to the relatively large gross exchange of CO2 between atmosphere and soils and the significant stocks of carbon in soils, relatively small changes in these large and opposing fluxes of CO2, i.e. as result of land use (change), land management and climate change, may have significant impact on our climate and on soil quality. 8. Monitoring systems for changes in soil carbon – Currently, monitoring and knowledge on land use and land use change in EU27 is inadequate for accurate calculation of changes in soil carbon contents. Systematic and harmonized monitoring across EU27 and across relevant land uses would allow for adequate representation of changes in soil carbon in reporting emissions from soils and sequestration in soils to the UNFCCC. 9. EU policies and soil carbon – Environmental requirements under the Cross Compliance requirement of CAP is an instrument that may be used to maintain SOC. Neither measures under UNFCCC nor those mentioned in the proposed Soil Framework Directive are expected to adversely impact soil C. EU policy on renewable energy is not necessarily a guarantee for appropriate (soil) carbon management

Exchange of radiatively active trace gases in tundra environments, with particular attention to methane

This thesis is concerned with trace gas flux in tundra environments, the main subject of study being methane. Methane emission from tundra soils has in recent years attracted increasing attention due to the possible associated feed-back effect on man-made climate change. The presented data are primarily produced. during field work in Northern Alaska but it also includes work in Northern Sweden and laboratory studies in Copenhagen. Model experiments carried out on basis of the gathered data was carried out in cooperation with the Hadley Centre at the Meteorological Office in England. Chapter 1 describes the area of research and the general background for embarking on the project. It concludes by defining a number of questions which the research presented in the thesis will attempt to answer. The first two chapters in the main body of the thesis (Chapter 2 and 3) fonn an introduction to tundra ecology with emphasis on aspects which are directly related to controls on soil emission of trace gases. It is explained how trace gas balances of tundra soils primarily are climatically controlled. These dependencies form main subjects of study in the thesis. Chapters 4 and 5 contain an analysis of methane emission from tundra environments primaiily based on field work in Alaska and Sweden but also involving laboratory studies of soil cores from a boreal bog. The bulk of the data presented are flux measurements produced using a static chamber technique. Methane and carbon dioxide were also analysed for their isotopic signatures. The scale of methane emission and factors controlling the flux at temporal and spatial scales are investiga!ed and discussed in relation to the info1mation available in the literature. After identifying the controlling factors most useful as tools for predicting methane emission the thesis moves on to describe an attempt to model seasonal variations in flux at the main tundra site investigated (Chapter 6). This model forms prut of the Meteorological Office climate prediction programme. The model is used in a number of climate change experiments in order to assess the possible feed-back effect from tundra methane emission following different climate change scenarios. Finally a simultaneous multigas analysis of carbon dioxide, methane, nitrous oxide and carbon monoxide flux in a tundra environment is described (Chapter 7). This forms basis for a discussion of the potential for the tundra to play a significant role in the atmospheric budgets of these gases. In a concluding chapter the questions defined in Chapter 1 are answered based on the work presented in the six preceding chapters.Digitisation of this thesis was sponsored by Arcadia Fund, a charitable fund of Lisbet Rausing and Peter Baldwi

Perspectives and Integration in SOLAS Science

Why a chapter on Perspectives and Integration in SOLAS Science in this book? SOLAS science by its nature deals with interactions that occur: across a wide spectrum of time and space scales, involve gases and particles, between the ocean and the atmosphere, across many disciplines including chemistry, biology, optics, physics, mathematics, computing, socio-economics and consequently interactions between many different scientists and across scientific generations. This chapter provides a guide through the remarkable diversity of cross-cutting approaches and tools in the gigantic puzzle of the SOLAS realm. Here we overview the existing prime components of atmospheric and oceanic observing systems, with the acquisition of ocean–atmosphere observables either from in situ or from satellites, the rich hierarchy of models to test our knowledge of Earth System functioning, and the tremendous efforts accomplished over the last decade within the COST Action 735 and SOLAS Integration project frameworks to understand, as best we can, the current physical and biogeochemical state of the atmosphere and ocean commons. A few SOLAS integrative studies illustrate the full meaning of interactions, paving the way for even tighter connections between thematic fields. Ultimately, SOLAS research will also develop with an enhanced consideration of societal demand while preserving fundamental research coherency. The exchange of energy, gases and particles across the air-sea interface is controlled by a variety of biological, chemical and physical processes that operate across broad spatial and temporal scales. These processes influence the composition, biogeochemical and chemical properties of both the oceanic and atmospheric boundary layers and ultimately shape the Earth system response to climate and environmental change, as detailed in the previous four chapters. In this cross-cutting chapter we present some of the SOLAS achievements over the last decade in terms of integration, upscaling observational information from process-oriented studies and expeditionary research with key tools such as remote sensing and modelling. Here we do not pretend to encompass the entire legacy of SOLAS efforts but rather offer a selective view of some of the major integrative SOLAS studies that combined available pieces of the immense jigsaw puzzle. These include, for instance, COST efforts to build up global climatologies of SOLAS relevant parameters such as dimethyl sulphide, interconnection between volcanic ash and ecosystem response in the eastern subarctic North Pacific, optimal strategy to derive basin-scale CO2 uptake with good precision, or significant reduction of the uncertainties in sea-salt aerosol source functions. Predicting the future trajectory of Earth’s climate and habitability is the main task ahead. Some possible routes for the SOLAS scientific community to reach this overarching goal conclude the chapter

Modelling the carbon cycle of Miscanthus plantations: existing models and the potential for their improvement

The lignocellulosic perennial grass Miscanthus has received considerable attention as a potential bioenergy crop over the last 25 years, but few commercial plantations exist globally. This is partly due to the uncertainty associated with claims that land use change (LUC) to Miscanthus will result in both commercially viable yields and net increases in carbon (C) storage. To simulate what the effects may be after LUC to Miscanthus, six process-based models have been parameterised for Miscanthus and here we review how these models operate. This review provides an overview of the key Miscanthus soil organic matter models and then highlights what measurers can do to accelerate model development. Each model (WIMOVAC, BioCro, Agro-IBIS, DAYCENT, DNDC and ECOSSE) is capable of simulating biomass production and soil C dynamics based on specific site characteristics. Understanding the design of these models is important in model selection as well as being important for field researchers to collect the most relevant data to improve model performance. The rapid increase in models parameterised for Miscanthus is promising but refinements and improvements are still required to ensure model predictions are reliable and can be applied to spatial scales relevant for policy. Specific improvements, needed to ensure the models are applicable for a range of environmental conditions, come under two categories: 1) increased data generation and 2) development of frameworks and databases to allow simulations of ranging scales. Research into non-food bioenergy crops such as Miscanthus is relatively recent and this review highlights that there are still a number of knowledge gaps regarding Miscanthus specifically. For example, the low input requirements of Miscanthus make it particularly attractive as a bioenergy crop but it is essential that we increase our understanding of the crop’s nutrient re-mobilisation and ability to host N-fixing organisms in order to derive the most accurate simulations