B. Goodison’s research while affiliated with Servei Meteorològic de Catalunya and other places

The Climate and Cryosphere (CliC) Project is a core project of the World Climate Research Programme (WCRP) and is co-sponsored by WCRP, SCAR (Scientific Committee for Antarctic Research) and IASC (International Committee for Antarctic Research). The principal goal of CliC is to assess and quantify the impacts that climatic variability and change have on components of the cryosphere and the consequences of these impacts for the climate system. To achieve its objectives, CliC coordinates international and regional projects, partners with other organizations in joint initiatives, and organizes panels and working groups to lead and coordinate advanced research aimed at closing identified gaps in scientific knowledge about climate and cryosphere. CliC has advanced significantly over the last several years. This presentation will provide an update of recent developments of its research themes, highlighting regional projects and their results, including precipitation research and applications.

Legacy of the IPY 2007-2008 will take many forms, and one key legacy for the cryosphere is the development of a WMO Global Cryosphere Watch (GCW), a proposal welcomed by the 15th WMO Congress (May 2007). GCW involves research, monitoring, assessment, product development and prediction. It will cover all aspects of the cryosphere. GCW would contribute to WMO's integrated observing and information systems and the GCOS (Global Climate Observing System), like the Global Atmosphere Watch does. It will be an intergovernmental mechanism for supporting key cryospheric in situ and remote sensing observations implementing the recommendations of the IGOS Cryosphere Theme. GCW will provide reliable, comprehensive observations of the elements of the cryosphere through an integrated observing approach on global and regional scales, in collaboration with other international programmes and agencies. It will work with, and build on existing programs, such as the GTN-G and GTN-P (Global Terrestrial Networks for Glaciers / for Permafrost) and work with external partners such as space agencies and World Data Centers for Glaciology. GCW can provide an integrating mechanism required to ensure better quality data and metadata, comparison of algorithms, the means to provide the scientific community to predict the future state of the cryosphere, facilitate assessment of changes in the cryosphere and their impact, and use this information to aid the detection of climate change, and organize assessments of changes in regional and global components of the cryosphere to support decision making and policy development. GCW is envisioned to include "cold GAW-like stations" - key stations/sites working on a coherently agreed program on monitoring of changes in all components of the cryosphere, producing valuable long- term records, covering key areas of the globe with cryospheric observations. It will help existing elements function better and contribute to a global system, and will help IPY cryospheric projects to develop elements of a sustained cryospheric observing system. A goal is to provide a one-stop portal for authoritative cryosphere data and products/information on the current state and projected fate of the cryosphere for use by the media, public, decision and policy makers. This presentation will update the status of GCW, consultations with scientists and agencies and at specialty workshops and the next steps in scoping the initiative

The cryosphere is an important and dynamic component of the global climate system. The global cryosphere is changing rapidly, with changes in the Polar Regions receiving particular attention during the International Polar Year 2007-2008. The Climate and Cryosphere (CliC) Project is a core project of the World Climate Research Programme (WCRP) and is co-sponsored by WCRP, SCAR (Scientific Committee for Antarctic Research) and IASC (International Committee for Antarctic Research). The principal goal of CliC is to assess and quantify the impacts that climatic variability and change have on components of the cryosphere and the consequences of these impacts for the climate system. To achieve its objectives, CliC coordinates international and regional projects, partners with other organizations in joint initiatives, and organizes panels and working groups to lead and coordinate advanced research aimed at closing identified gaps in scientific knowledge about climate and cryosphere. CliC has advanced significantly over the last several years. This presentation will provide an update of recent developments of its research themes, highlighting regional projects and their results, interaction and collaboration with other international projects, and outlining the future direction of the CliC project.

Within Earth Sciences many of the disciplines relevant to hydrology and even hydrological sciences itself are disperse when dealing with cold climates/regions of the world. The links between cold region hydrology and temperate or tropical climate zones are weak or even lacking. Geographically, the links are missing between high latitude /cold region hydrology and high altitude/mountain hydrology. To understand global (climate) changes and its effect on water resources this gap needs to be bridged. Most of our fresh water resources originate in mountainous regions and/or cold regions. Changes in these environments lead to hydrological implications for water resources management which are currently poorly understood and not very predictable on any time and spatial scale. This gap is recognised within international science programmes such as the Global Energy and Water Cycle Experiment (GEWEX), and the Climate and Cryosphere Project (CliC), both part of the World Climate Research Programme (WCRP). Even extremely important initiatives such as the International Polar Year (IPY) or Northern Eurasian Earth Science Partnership Initiative (NEESPI) do not fully bridge this gap. A new initiative, High Altitude - Latitude Hydrology will bring together, different disciplines, various research communities and individual scientists to help bridge this gap. This should lead to more visibility of critical issues with funding agencies and is expected to result in an increase in expertise, knowledge and increased technological and experimental capability.

The Climate and Cryosphere Project is sponsored by the World Climate Research Program (WCRP) and the Scientific Committee for Antarctic Research (SCAR). One of the four themes within the CliC project is the Marine Cryosphere Theme (MarC). This paper will review the recent projects and workshops held within this Theme and how they relate to other, international initiatives. Recent recommendations on sea ice thickness are being implemented, and groups have been formed to work towards improvements in models, particularly in their representation of the Southern Ocean. SOPHOCLES (Southern Ocean Physical Oceanography and Cryosphere Processes and Climate) will work with other modeling groups to improve the representation of the Southern Ocean in climate models. This will include cooperation with other modeling and observational groups to develop metrics to help evaluate models. In the Arctic, we are working to help develop, standardize, and implement observation and measurement protocols for Arctic sea ice in coastal, seasonal, and perennial ice zones.

Snow cover is spatially heterogeneous at the local scale because of micro climatic, topographic and vegetative effects on snow accumulation, redistribution and ablation ‐ processes which vary between different environments. Automated, fixed point snow depth measurements are the norm at research as well as operational sites, and the ability of these single point measurements to characterize snow depth for the surrounding area is an important issue. In this study, data for three winter seasons (2002–03, 2003–04, 2004–05) from ten Boreal Ecosystem Research and Monitoring Sites (BERMS) in northern Saskatchewan were used to assess the relationships between local scale snow depth variability, ascertained from snow survey transects, and single point measurements made with sonic depth sensors.Analysis of the snow surveys showed a wide range of depths at each site, with increased variability as winter progressed. Single, fixed‐point measures of snow depth did not statistically represent the average snow depth at a site, even for relatively uniform snow covers. Consistent over‐ or under‐representation of the landscape mean allowed the development of a “scaling equation” for each point measurement, improving confidence in the use of these data for modelling and climate variability studies. Where manual snow surveys may not be practical, the use of multiple automated point depth measurements may be adopted, and for the BERMS sites it was found that the minimum number of point measurements required to represent the landscape mean within 25% ranged from 1 to 44, depending on the degree of variability in snow depth associated with the landscape type, and the magnitude of the site mean depth. The relationships between point snow depth measurements and mean areal snow depth are important to consider both when utilising historical point observations for climatological and hydro‐logical analysis, and for decision‐making with regards to snow depth observing networks.

Snow cover is encountered over most of the Northern Hemisphere (NH) mid- and high-latitudes during the winter season and over many mountainous regions of the world for extended periods. Snow cover is an important component of the climate system through its role in modifying energy and moisture fluxes between the surface and the atmosphere, and through its role as a water store in hydrological systems. Snow also plays critical roles in ecological and biological systems, and in nutrient and carbon cycling. This article provides an introductory overview of snow cover including: definition of terms (snowfall, solid precipitation, snow depth, snow density, snow water equivalent); a review of methods for measuring snow cover properties; a discussion of the processes and concepts involved in the spatial and temporal variability of snow cover; a look at avalanches and recent efforts to model these; and finally, a discussion of how snow cover is changing in response to global warming. Keywords: snow; snow cover; snow depth; snow density; snow water equivalent; snow measurement

A consistent daily bias correction procedure was applied at 4802 stations over high latitude regions (North of 45°N) to quantify the precipitation gauge measurement biases of wind-induced undercatch, wetting losses, and trace amount of precipitation for the last 30 years. These corrections have increased the gauge-measured monthly precipitation significantly by up to 22 mm for winter months, and slightly by about 5 mm during summer season. Relatively, the correction factors (CF) are small in summer (10%), and very large in winter (80-120%) because of the increased effect of wind on gauge undercatch of snowfall. The CFs also vary over space particularly in snowfall season. Significant CF differences were found across the USA/Canada borders mainly due to differences in catch efficiency between the national gauges. Bias corrections generally enhance monthly precipitation trends by 5-20%. These results point to a need to review our current understanding of the Arctic fresh water budget and its change.

Composite patterns of monthly averaged (1978–2002) satellite passive microwave derived snow water equivalent (SWE) data produced using the Meteorological Service of Canada land cover sensitive algorithm suite contain an interannually consistent and well-defined zone of high SWE retrievals (> 100 mm) across the northern boreal forest of western Canada. Consistently lower SWE retrievals are present across both the comparatively dense boreal forest to the south, and open tundra to the north. Because of the sparse conventional observing network across this region, a dedicated field sampling campaign was conducted during the 2003/2004 winter season to measure snow properties across these landscape zones in northern Manitoba, Canada. Using road and helicopter access, snow cover measurements were made along an approximately 500 km transect between the communities of Thompson (boreal forest), Gillam (sparse northern boreal forest), and Churchill (open tundra) during late November 2003, and early March 2004.

New multiscale research datasets were acquired in central Saskatchewan, Canada during February 2003 to quantify the effect of spatially heterogeneous land cover and snowpack properties on passive microwave snow water equivalent (SWE) retrievals. Microwave brightness temperature data at various spatial resolutions were acquired from tower and airborne microwave radiometers, complemented by spaceborne Special Sensor Microwave/Imager (SSM/I) data for a 25×25 km study area centered on the Old Jack Pine tower in the Boreal Ecosystem Research and Monitoring Sites (BERMS). To best address scaling issues, the airborne data were acquired over an intensively spaced grid of north-south and east-west oriented flight lines. A coincident ground sampling program characterized in situ snow cover for all representative land cover types found in the study area. A suite of micrometeorological data from seven sites within the study area was acquired to aid interpretation of the passive microwave brightness temperatures. The in situ data were used to determine variability in SWE, snow depth, and density within and between forest stands and land cover types within the 25×25 km SSM/I grid cell. Statistically significant subgrid scale SWE variability in this mixed forest environment was controlled by variations in snow depth, not density. Spaceborne passive microwave SWE retrievals derived using the Meteorological Service of Canada land cover sensitive algorithm suite were near the center of the normally distributed in situ measurements, providing a reasonable estimate of the mean grid cell SWE. A realistic level of SWE variability was captured by the high-resolution airborne data, showing that passive microwave retrievals are capable of capturing stand-to-stand SWE variability if the imaging footprint is sufficiently small.