Transcript Liz Kent
CCl/CLIVAR/JCOMM ETCCDI Workshop De Bilt 13-15 May 2008 Climate Indices from Marine Data Workshop illustrates that most studies focus on land T and P: need for marine indices Elizabeth Kent - National Oceanography Centre, Southampton Val Swail - Environment Canada, Toronto Scott Woodruff - NOAA Earth System Research Laboratory, Boulder David Parker - Met Office, Exeter FOCI ANTICIPATED FOR MARINE INDICES • detection and attribution of climate change • impact on marine industries (fishing, shipping, oil and • • • • • • • gas production, tourism) sea-level change marine hazards (extreme winds and waves, harmful algal blooms, pollution) changes in hydrological cycle changes in ocean circulation changes in sea ice and ice bergs effects on coastal communities ocean acidification MARINE DATA SOURCES AND PROGRAMS • • • • • • • ICOADS – ships (from 1662), moored and drifting buoys World Ocean Database (WOD) Global Digital Sea Ice Data Bank (GDSIDB) Permanent Service for Mean Sea Level (PSMSL) Derived data sets – HadISST, HadSLP, HadGOA (www.hadobs.org ) Satellite – SST, wind, wave, ice, sea level Reanalyses • • • • • • • • Ship Observations Team Data Buoy Cooperation Panel Argo Ocean Sites Global Sea Level Observing System International Ocean Carbon Coordination Project Global Temperature and Salinity Profile Program JCOMMOPS (www.jcommops.org ) Integrated Ocean Observing System Ship observations ASAP Drifting buoy Argo Sea level Moorings Annual numbers of marine reports in ICOADS, stratified by platform type for 1936 to 2005 (Woodruff et al. 2008) ICOADS Sampling by Parameter Perspective on Historical Data • JCOMM Expert Team on Marine Climatology links with International Comprehensive OceanAtmosphere Data Set (ICOADS) • Recovery of more data & metadata: key to improving past climatologies, e.g. Recovery of Logbooks And International Marine data (RECLAIM) Improvements to ICOADS • Many new data sources added to ICOADS focused on data sparse regions and periods. ICOADS Improvements in 1930s The potential for marine indices Operational Resources required Large scale pressure (e.g. NAO, PNA) Large scale temperature (e.g ENSO) Sea Ice parameters Temperature indices Ocean heat content Sea level Marine winds and pressures Waves Research required Atlantic Meridional Circulation Currents Max & min temperatures Wind gusts Polar lows. Storm surges Hydrographic time series (e.g. ICES) Salinity measures Fisheries information & biology Ocean transports and Ocean chemistry water mass (e.g. dissolved properties oxygen) Hurricanes Deep convection Clouds, humidity. Data required Extremes Precipitation Ph/Ocean Acidification Temperature trend over 1901-2003 Monthly Surface Temperature Sept. 2006 Anomalies Percentiles Tropical Central and EastPacific SST Anomalies, 1850-2005 Hadley Centre for Climate Prediction and Research 12 Global Wave Climatology Atlas S. Caires, G. Komen, A. Sterl, V. Swail www.knmi.nl/waveatlas Monthly mean wind speed Monthly mean sig. wave height 1966 Number of gridpoints Number of gridpoints 1966 Year of changepoint Year of changepoint Number of gridpoints of a significant changepoint in the indicated year Wind speed – locations of changepoint in Nov. 1966 Sig. wave height – location of changepoint in Nov. 1966 x x Grid-boxes of significant changepoint are shown in black MSC50 Wind and Wave reanalysis 1954-2007 Annual sea-ice extent changes, 1973-2006 (updated from IPCC, 2001) Antarctic sea-ice Not declining since 1976 Arctic sea ice Retreating until late1990s. Little retreat 1998-2003 Hadley Centre for Climate Prediction and Research 15 Background: ocean heat uptake Heat content for Anomaly for the upper 300m See Gregory et al. [2004] © Crown copyright Changes in mean T and isotherm depths Deepening of isotherms in N. Atlantic associated with change in phase of NAO. Mean 14C isotherm depth Large areas of slight shoaling and smaller areas of large deepening 1985-2004 minus 1961-1980 Wide-spread warming signal. Less prone to aliasing from changes in ocean circulation than z-levels. Mean T above 14C isotherm © Crown copyright Greater insight into underlying physical mechanisms Enabling Mechanisms ICOADS - Critical and critically under-resourced Proposed new initiative for value-added ICOADS (QC, bias corrections, etc.) JCOMM Expert Teams Wind Waves and Storm Surges Sea Ice Marine Climatology Task Team on the Marine-meteorological and Oceanographic Summaries (TT-MOCS) Task Team on Delayed-Mode VOS (TT-DMVOS) Engage expertise within the CLIMAR community to assist in the development and production of marine indices (marineclimatology.net) Liaise with other groups interested in marine indices such as the AOPC and OOPC Prediction of changes in the ocean is vital for prediction of extremes over the land. Marine focus has been on the creation of high quality gridded data sets with uncertainty estimates Many similar issues to land inhomogeneity sampling Many variables of interest – and multivariate analyses Difficult to calculate high-percentile extremes due to data uncertainty.