Gabriel Lau Geophysical Fluid Dynamics Laboratory/NOAA Princeton University Heat Waves and Climate Change

Midwest Heat Waves Model Observations Surface Temperature Precipitation °C mm/dy

Midwest Heat Waves Model Observations 500mb Geopotential Height Sea-level Pressure / Surface Wind mb m

ObservationModel Model Model Ratio: vs Severity (°C) Duration (days) Number of Events per year Number of Heat Wave days per year Midwest Heat Waves

Duration# Events/yr# Heat wave days/yr Midwest Northern Plains Pacific Northwest SE Canada Texas-Oklahoma Mid-Atlantic California Gulf Coast Southwest Wyoming/Montana/ Idaho Model Projections Ratio: vs

Severity ( o C) Duration (days) Frequency (# heat waves per yr) # Heat Wave Days Per Year Central Great Plains Northern Great Plains

Geophysical Fluid Dynamics Laboratory Coherent Regions of Surface Temperature Variability

Geophysical Fluid Dynamics Laboratory Circulation and Precipitation Patterns Accompanying Heat Waves in Region 2 mm d -1

Geophysical Fluid Dynamics Laboratory RCP 4.5RCP 8.5 Observation Model Model Model Ratio: vs Model Model Ratio: vs Duration (days) Number of Events per year Number of Heat Wave days per year Heat Waves in Region 2

Geophysical Fluid Dynamics Laboratory Duration# Events/yr# Heat wave days/yr Region Region Region RCP 4.5 Model Projections Ratio: vs Duration# Events/yr# Heat wave days/yr Region Region Region RCP 8.5

European Heat Waves Mode 1 Mode 2 Surface Temperature Precipitation mm day -1 oCoC

European Heat Waves Mode 1 Mode mb Height SLP / Surface Wind mb m

Geophysical Fluid Dynamics Laboratory/NOAA Princeton University Thank You