Global Change: New Operations and Modeling Challenges Ants Leetmaa Geophysical Fluid Dynamics Laboratory National Oceanic and Atmospheric Administration Princeton, NJ

OVERVIEW Grand Challenges for 21 st Century population growth altered biogeochemical cycles a changing climate A prototype forecast in 2030 Existing capabilities to meet the challenge Institutional challenges for the NWS and NOAA

Population Growth and Associated Issues 9 billion (B) people by 2050 (50% increase) Increasing urbanization into mega-cities – 4B new city dwellers – aging populations Food availability requires sustainable increases in food output/hectare of % Energy & Security Others Water availability health threats – pollution, others

Drier Wetter Annual change in runoff (cm/yr) Possible Global Warming Impacts Annual Surface Air Temperature (deg C) Conditions at double pre- industrial values of CO2: GFDL model Summer Soil Moisture (cm) Winter runoff (cm/yr) These changes will present new opportunities and threats

Possible Hazards -Summer 2030: hot, dry and unhealthy ( after 7 th consecutive year of droughts) Swimming and Fishing prohibited African bacteria alertsExpect fisheries downturn; health threats Health warning: Limit outdoor activities; expect brownouts Frequent floodings and Asian dust threats continue Major fires Agricultural production at 50%, blowing dust major fisheries regime change likely Air quality alerts – 75% of days High danger of toxic CO2 releases ALERT FORECASTs: US Economy – code orange; US health – code orange; International Economy – code red: Global Security – code red

Next Generation Forecast Products Seasonal biomass production Drought with interactive vegetation Global atmospheric chemical transports Health impacts including effects of global and local aerosol & ozone transports, biomass emissions, and temperature Sea level - flooding Coastal ecosystem health Fisheries and ecosystem regime change likelihoods Geo-engineering accidents

Extending the Product Suite: Institutional Challenges Your focus on current product delivery will limit investment in new areas New products entail risks Technology progresses faster than NOAA Challenge for NOAA is to develop a common architecture to foster transition to NOAA-next.

Some Issues to Ponder What will be NOAA’s most important future product suites? (hint – economy, health, environment) How will you develop the appropriate modeling and product delivery mechanisms? (hint – it won’t all be done in house) How are you going to work with the rest of NOAA to meet these future challenges

The U.S. Experiences Strong Decadal Fluctuations in Climate Wintertime Surface Temperature Anomalies (deg. C) These resulted from Natural climate variability Anthropogenic causes Volcanic and solar effects Major features were Warm 1950’s and 1990’s Cool 1960’s and 1970’s

NOAA Uses Computer Models to Develop a Predictive Understanding of Climate Fluctuations GFDL’s model simulates U.S. temperature changes when forced with observed ocean temperatures - same model is used for ENSO fcsts Observed Model

Improved Predictive Understanding Leads to a Decadal Forecasting Capability and Increased Confidence in Global Warming Projections Model forced with observed ocean temperatures A “prediction” starting in 1860 forced with observed radiative forcings - note cool 60s&70s with rapid warming in 1990s

Decadal Average Wintertime Temperature Anomaly for U.S. (deg C.) Observed - determined from atmospheric reanalysis Simulated - model forced with observed ocean temperatures Predicted - model forced with greenhouse gases, volcanoes, solar fluctuations from 1860 to present

Seasonality of Long Term Temperature Trends

Seasonality of Model Projections Seasonality and spatial structure of warming similar in model runs and observations Model runs started in 1860 and run forward with “observed’ forcings (GHGs, aerosols, solar, ozone)

Summary A richness of tropical forced responses are important on a variety of time scales, e.g. ENSO like physics remains important Hadley and Walker cells slow down with global warming Tropical convection becomes more zonally symmetric Seasonal circulation patterns become more zonally symmetric Subtropical highs expand northward (or southward)– especially summer/fall – depending on warming (or cooling) of tropics Mid-latitudes experience greater drying tendencies with warming Models are starting to be capable of explaining decadal and regional climate variability this will enable more credible attribution (anthropogenic or natural variability) of longer term trends ENSO temporal structure doesn’t change significantly Suggestion of stronger and longer duration events with warming – predictability possibly is greater Increased chances of more “100 year” events Teleconnection patterns are more robust with warming Decadal variability of ENSO can confound warming signal and is important in decadal mid-latitude climate fluctuations (droughts, etc.)

End

Predictability of Atmospheric Variations: Present and Future Tony Rosati and Gabriel Vecchi Geophysical Fluid Dynamics Laboratory NOAA/OAR Princeton, NJ 08542

Climate Scenarios Being Run for 2007 IPCC What can we learn from these about the slow and fast modes of climate variations?

Preliminary Results from IPCC 2007 Runs The slow modes - changes to the general circulation Hadley and Walker cells Season means The fast modes -impacts of change on climate variability (ENSO)

Changes to Hadley and Walker Circulations 2x Mean 4x minus 1860 % change Slow down of tropical/subtropical circulations associated with redistributions of tropical rainfall ( 500 mb vertical velocity field) 2X

Changes in Mean Annual Cycle: DJF Surface temperature rainfall Z200U200 Note the development of a zonally and hemispherically symmetric component to the circulation anomalies – with strong impacts in midlatitudes

Surface temperature rainfall Z200U200 The poleward expansion of the subtropical highs is most pronounced in fall and summer relative to 1990 shows equatorward movement of highs. Changes in Mean Annual Cycle: SON

Seasonality of Model Projections Seasonality and spatial structure of warming similar in model runs and observations Model runs started in 1860 and run forward with “observed’ forcings (GHGs, aerosols, solar, ozone)

Changes to Tropical Variability with Planetary Warming reversed 1860 spinup1990 CO 2 CO 2 increasing 1%/yr NINO3 SST Power Spectrum Increasing CO2 Period (yr) 135yr

NINO3 SST Spectrum Changes Period (years) greenhouse obs

Changes to Spatial Structure and Amplitude of ENSO (As evidenced in 500 mb vertical velocity field) 2X 4X

Changes in Amplitude of ENSO Teleconnections: DJF