Within the last 25 years a remarkable increase of the Arctic near–surface air temperature exceeding the global warming by a factor of two has been observed. This phenomenon is commonly referred to as Arctic Amplification. The warming results in rather dramatic changes of a variety of Arctic climate parameters. For example, the Arctic sea ice has declined significantly. To study processes leading to Arctic Amplification we combine the scientific expertise and competency of three German universities (Leipzig, Bremen, Cologne) and two non–university research institutes (AWI, TROPOS) in the framework of a Transregional Collaborative Research Centre TR 172 (http://ac3-tr.de/) funded by the German Research Foundation (DFG). The first approved funding period (Jan 2016 to Dec 2019) covers the time frame of YOPP. The project will deliver a major German contribution to MOSAiC. Observations from instrumentation on satellites, aircraft, tethered balloons, research vessels, and a selected set of ground–based sites will be integrated in dedicated campaigns, as well as being combined with long–term measurements. The field studies will be conducted in different seasons and meteorological conditions, covering a suitably wide range of spatial and temporal scales. They will be performed in an international context and in close collaboration with modelling activities. The latter utilize a hierarchy of process, meso–scale, regional, and global models to bridge the spatio–temporal scales from local individual processes to appropriate climate signals. The models will serve to guide the campaigns, to analyse the measurements and sensitivities, to facilitate the attribution of the origins of observed Arctic climate changes, and to test the ability of the models to reproduce.
The project addresses the combination of earth observation (EO) data streams with a numerical model of the Arctic ocean sea-ice system using advanced data assimilation techniques. The team proposes to construct a highly flexible system for Arctic Mission Benefit Analysis (ArcMBA) that evaluates in a mathematically rigorous fashion the observational constraints through individual and groups of EO (and in situ) data products in an advanced data assimilation system. A+5 fits to the YIOO objective on the improvement of polar prediction capabilities on daily to seasonal time scales.
The project seeks to improve our understanding of physical processes in the Arctic and specifically to explore what it would take to reduce the risk of summer sea-ice completely disappearing within this century. The tools to achieve this will be improved modeling across the scales from hemispheric to local and especially for the surface energy balance and clouds, and improved process-level research-grade observations by building a semipermanent atmospheric observatory on the Swedish icebreaker Oden.
Aerosol-cloud interactions are the least understood anthropogenic influence on climate change (IPCC, 2013). A major cause of this limited understanding is the poorly quantified state of aerosols in the pristine preindustrial atmosphere, which defines the baseline against which anthropogenic effects are calculated. The uncertainty in aerosol induced radiative forcing (± 0.7 from a mean of -0.55 W/m2) is twice the uncertainty for CO2 (± 0.35, mean +1.68 W/m2). Also, models grossly underestimate cloud solar reflectance there, by as much as 30 W/m2 during summer. We suspect it partly being due to poor representation of aerosol-cloud interactions.
This project aims at reducing the uncertainty in the effects of aerosols on climate change by exploring preindustrial-like conditions which can almost only be found in the Southern Ocean. To achieve this, we will conduct ship-based measurements of aerosol microphysical and chemical characteristics as well as measurements of trace gases modulating particle characteristics and combine these with on-board remote sensing and satellite data of clouds to evaluate global climate models.
The Southern Ocean is the most pristine aerosol environment on Earth, but almost the entire region remains unsampled. The ACE expedition from December 2016 to March 2017 provides a unique and unprecedented opportunity to prove or dismiss this hypothesis.
A suite of cloud, aerosol and radiation instruments will be deployed to Macquarie Island (54°S) Davis (69°S), and onboard the Australian icebreaker (43°S - 69°S). The data collected will be used to validate satellite cloud retrievals; evaluate weather forecasting and climate models; and aid in model development. ARM deployments to Macquarie Island (MICRE, 2016-18) and onboard the Australian icebreaker (MARCUS, summer 2017-18 season) are a key component of this research project.
A high-resolution coupled atmosphere-cryosphere-ocean model will be developed and used in the Adélie Land area, Antarctica to evaluate the impacts of the high spatial and temporal resolution, explicit treatment of small-scale processes usually neglected or highly parameterized in global climate models, and coupling on the sea ice characteristics, the air-ice-ocean interactions, and the surface mass balance of the Antarctic ice sheet on daily to seasonal time scales. The effect of initial conditions on the model prediction skill will also be assessed.
ALERTNESS will significantly improve AROME Arctic, the recent entry-into-service weather forecast model system at MET Norway. It is an operational convection-permitting model system dedicated to the European Arctic and one of the core models of the Year of Polar Prediction (YOPP). The project will advance challenges unique for the Arctic: The sparse conventional observation network, exploitation of satellite observations over snow and ice, atmospheric data assimilation at high latitudes, parameterization and representation of key polar processes, and the associated representation of uncertainties. The project is led by MET Norway, with co-leads from University of Bergen, the University Centre in Svalbard (UNIS), and Uni Research.
This project builds upon an existing one being led by Atkinson. The intent is to continue working towards improved marine weather and storm information and preparedness for ocean waves, swell and storm surge for coastal communities (Ulukhaktok, Tuktoyaktuk and Sachs Harbour) and marine operations in the western Canadian Arctic.
The main focus of the project Antarctic precipitation properties from ground-based instruments (APP) is to set up an observatory for investigating precipitation in Antarctica. Characterization of effective precipitation that occurs at ground of Antarctica region, plays a crucial rules in defining and validating global climate models and numerical weather prediction model. The observatory is designed to be set up at the Italian Antarctic station Mario Zucchelli integrating the current instrumentation for weather measurements with other instruments specific for precipitation observations. In particular, a 24-GHz vertical pointing radar, Micro Rain Radar, and an optical disdrometer, Parsivel will be integrated with the advanced weather stations, radiosoundings and the ceilometer. The synergetic use of the set of instruments allows for characterizing precipitation and studying properties of Antarctic precipitation such as dimension, shapes, fall behavior, density of particles, particles size distribution, particles terminal velocity, reflectivity factor and including some information on their vertical extent. The project is for four years, it started in July 2017 and will be active until July 2020, covering the Special Observation Period (SOP) in the Southern Hemisphere of Year of Polar Predicition (YOPP) period. APP can be provide specific measurements for precipitation occurring over the Antarctic coast at high temporal resolution, in particular specific snow products such as snow rate, snow depth and their water equivalent.
APPLICATE will develop enhanced predictive capacity for weather and climate in the Arctic and beyond, and
determine the influence of Arctic climate change on Northern Hemisphere mid-latitudes, for the benefit of
policy makers, businesses and society.
Antarctic Precipitation, Remote Sensing from Surface and Space (APRES3) is a program to acquire in situ data to characterize precipitation in Antarctica (rate, size and shape of falling snow), use the data to calibrate, validate and contribute improve satellite climatology, improve cold microphysics of water condensation in meteorological and climate models, evaluate and validate the models using satellite climatology, and finally run forecasts of precipitation changes and impact on sea-level, in time to contribute IPCC6.
Interactions in the Arctic atmosphere-sea-ice-ocean system change the circulation/dynamics/heat in the ocean and lower atmosphere, and the thickness/distribution of sea-ice and snow. Autonomous, integrated atmosphere-ice-ocean buoy systems have been developed to provide year-round observations from the harsh and hard to access Arctic Ocean. In addition to giving a quasi-synoptic view on regional scales, these systems allow an in-depth study of local processes. Satellite observations allow additional synoptic insight and need to connect observational scales. Building on our expertise we propose to study key local processes involving sea-ice-atmosphere-ocean interaction in a large-scale context. In addition to synthesising existing autonomous observations and satellite data products in scientific analyses, the work will feedback with buoy-related programmes and support the upcoming international drift campaign MOSAiC. This project will support YOPP by evaluation of near-real-time observational systems in a long-term context.
Arctic ice has declined during the last decade, and possibly related unprecedented abnormal midlatitude weather has been reported. There is evidence that a more complete Arctic observing system will improve tropical cyclone track forecast in the mid latitudes. Arctic observations require urgent research efforts for effective planning to prevent or mitigate potentially large societal and economic losses.
In this project, effective observation system in the Arctic region to improve Arctic and mid-latitude extended-range forecasts will be investigated using Observing System Simulation Experiments (OSSEs). Global and Regional OSSEs and theoretical prediction can provide complementary information about requirements for future Arctic observing systems. First, OSSEs with global coverage will be conducted at relatively low resolution, and resolution will then be varied to evaluate how the observation impact depends on the model resolution and various configurations. The impact of higher resolution will be investigated with regional OSSEs with advanced physics over the Arctic.
Simulated experiments with idealized observations will be conducted in the initial stage. Idealized observations are designed based on the distribution of planned potential observing systems without current technical limitations.
The task will be accomplished by making the best use of the recently developed US operational weather forecast system including the Next Generation Global Prediction System (NGGPS). The Nature Run (NR), simulated ‘truth’ for the OSSEs, which is most suitable for this project, is being prepared.
Arctic PASSION aims to implement an integrated pan-Arctic observing system of systems. This will be achieved by refining its operability, improving and extending pan-Arctic scientific and CBM systems and services, streamlining the access and interoperability of Arctic Data systems, and providing the economic viability and sustainability of the observing system. By working in partnership with key rights holders we will unify and extend the presently fragmented Arctic observing system in collaboration with Copernicus and ESA, as well as relevant international programmes. One key element of our legacy will be the fulfillment of an ArcticGEO initiative with SAON. We will
• enhance and better integrate Arctic observations of the terrestrial, atmospheric and oceanic environment, including Indigenous and Local Knowledge and CBM, to extend the present observation network into a requirement-driven, adaptive system that better serves societal needs,
• improve Arctic data management enhancing handling, archiving and interoperability of environmental data,
• optimize Arctic Observing networks through modeling techniques utilizing statistical and numerical modelling to improve the impact of specific observing system on monitoring and forecasting capabilities,
• deliver set of innovative EuroGEO services for the Arctic by co-developing crucial Pilot Services with different types of users to satisfy Arctic information needs and to improve safety and emergency preparedness.
• quantify the societal benefit of a pan-AOSS and enhance International Collaboration, strengthening European and international integration and coordination,
• provide decision making and policy support establishing meaningful dialogues with local to international policy makers for relevant policy impact.
Large investments are currently made to improve mapping, monitoring, observing and surveying capabilities in the Arctic Ocean. These new technological infrastructures widen the range of available information. This provides a basis for the growth of informed economic activities, thus stretching the boundaries of the accessible Arctic. The information systems thereby seem to play a double role. While making the Arctic more controllable and predictable, they also enlarge the potential risks and hazards associated with increasing activity. The main objective of this project is to analyze the development of information systems in the Arctic and how they affect economic decision-making. In three thematic work packages, we (1) investigate the development of Arctic information systems as socio-technical infrastructures; (2) generate deeper understanding of the complexities and challenges in the user-producer interface in Arctic information systems; (3) and explore how Arctic information systems affect economic decision-making and alters the Arctic as a zone of risk.
Arctic sea ice has undergone rapid changes in the last decade as thick, multi-year ice has been melting and replaced with thin, more dynamically-fragile first-year ice. This, coupled with a strong trend towards reduced sea-ice extent has led to a transition towards a new, blue Arctic. This brings uncertainty for atmospheric and sea-ice forecasts in the region as many aspects of air-ice coupling are poorly understood on both the small-scale and the mesoscale.
In this project, we seek to improve our understanding of the importance of air-ice coupling processes for atmospheric and sea-ice forecasts by using a hierarchy-of-coupling approach. We will use an advanced sea-ice model with a realistic rheology, NeXtSIM, in combination with the Weather Research and Forecasting model and an interfacial atmospheric boundary layer model to assess coupling processes and their importance for atmospheric and sea-ice forecasts.
When rain falls on an existing cover of snow, followed by cold temperatures, or falls as freezing rain, it can leave a hard crust. Surface melt followed by cold can do the same. There is growing evidence that such events are becoming more common in the rapidly warming Arctic, and it is increasingly recognized that they can have pronounced impacts on Arctic wildlife, domesticated reindeer, and human activities, like travel.
Rain on snow events have sometimes resulted in large die-offs of reindeer because the icy crust makes it difficult for reindeer to find forage and their movements may be inhibited. The Arctic Rain on Snow Study (AROSS), a collaboration between the University of Colorado Boulder, the Alaska Pacific University, the University of Lapland and involving extensive community engagement and co-production of knowledge, seeks to better understand the distribution, severity, and changes in the frequency of rain on snow events and melt-refreeze events in the Arctic and their impacts, with a focus on hunting and in particular, reindeer herding livelihoods.
A primary objective of SCAR’s expert group Antarctic Sea ice Processes and Climate (ASPeCt: http://aspect.antarctica.gov.au/) is to establish the distribution of the basic physical properties of sea ice that are important to air-sea interaction and to biological processes within the Antarctic sea-ice zone. To achieve this goal, ASPeCt has established a data-acquisition strategy of maintaining an ongoing system of quantified shipboard observations that provides statistical descriptions of sea ice and snow thickness distributions. These observations of in-situ ice characteristics, made year after year, largely during the southern spring, summer and autumn, are crucial for monitoring and understanding the maritime climate system as well as for providing verification of satellite products and model output. These observations are directly relevant to the YOPP objectives outlined in the YOPP Implementation Plan. Therefore, ASPeCt proposes to contribute its acquisition strategy and the sea-ice data so acquired, to the YOPP effort to be used, for example, for model verification and improved representation of sea ice in models.
ASPIRE will address the Antarctic atmosphere and snow. The work will result in better understanding of physical processes as well as in parameterizations and post-processing methods applicable in weather prediction.