Melting Antarctic Ice: Hot Air or Chilling Reality? Dr. David Vaughan Hot Science - Cool Talks Volume 47 Produced by and for the Hot Science – Cool Talks Outreach Lecture Series of the Environmental Science Institute. We request that the use of any of these materials include an acknowledgement of Dr. David Vaughan and the Hot Science – Cool Talks Outreach Lecture Series of the Environmental Science Institute of the University of Texas at Austin. We hope you find these materials educational and enjoyable. Melting Antarctic Ice: Hot Air or Chilling Reality? David G. Vaughan British Antarctic Survey What goes on in Antarctica is important to the rest of the world West Antarctic Links to Sea Level Estimation Menu Menu • Overview of Antarctica • Human fingerprints on the last wilderness • Archive of Planet Earth • Climate change in Antarctica • Sea-level rise – life’s a beach, why worry? • Antarctica and sea-level rise • Getting out there • Science and policy – where next? Arctic and Antarctica are very different Three major environments M o s t o f A n t a r c t i c a l o o k s l i k e t h i s T h e i c e i s c o n s t a n t l y o n t h e m o v e 9 9 . 6 % o f t h e c o n t i n e n t i s c o v e r e d i n i c e g e r t h a t t h e h o m e c o u n t i e s o f E n g l a n d ( U S E Q U I V A L E N T ? ) , f o r c o l o n i s o z e n s e a w a t e r o n l y a m e t r e t h i c k ) e x p a n d s t h e a r e a o f A n t a r c t i c a e v But it is the ice sheet that dominates the continent Antarctica is the only continent that wasn’t explored in a temper! Menu • Overview of Antarctica • Human fingerprints on the last wilderness • Archive of Planet Earth • Climate change in Antarctica • Sea-level rise – life’s a beach, why worry? • Antarctica and sea-level rise • Getting out there • Science and policy – where next? Menu – human fingerprints on the last wilderness Radioactive Fallout FOOTPRINT 1. Radioactive fallout from above-ground nuclear bomb testing in the 1950s remains as horizon in the ice Lead pollution 1980 1970 1960 Lead buried in the snow 1950 1940 1930 1920 Concentration of Lead (ng / kg) 12 8 4 0 0 2 4 6 8 Firn depth / m Source: Wolff and Suttie Ozone Hole Ozone hole Source: NASA/BAS Menu – archive of planet earth Menu • Overview of Antarctica • Human fingerprints on the last wilderness • Archive of Planet Earth • Climate change in Antarctica • Sea-level rise – life’s a beach, why worry? • Antarctica and sea-level rise • Getting out there • Science and policy – where next? B u b b l e i m a g e The ice-core record Vostok Core (black) and Dome C Core (blue) Dome C Core The ice-core record Vostok Core (black) and Dome C Core (blue) Thousands of years before present Source: EPICA Menu • Overview of Antarctica • Human fingerprints on the last wilderness • Archive of Planet Earth • Climate change in Antarctica • Sea-level rise – life’s a beach, why worry? • Antarctica and sea-level rise • Getting out there • Science and policy – where next? Menu – climate change in Antarctica Climate change - World perspective Source: IPCCWorking Group I, Summary for Policymakers, 2007 Trend in Average Annual Global Temperatures (1955 to 2005) 0.59 oC Climate change World perspective -2.1 -2 -1.5 -1 -.5 -.1 .1 o .5 1 1.5 2 2.9 C Source: Hansen Trends in mean annual temperature Temperature trend (oC) Climate change in Antarctica Longitude Climate change in Antarctica – trends in mean annual temperature Source: Vaughan et al., 2004 Antarctic Peninsula Trend in annual temperature Mean annual temp (oC) Antarctic Peninsula – trend in annual temperature Date Source: King et al., BAS Trends in sea-ice duration around Antarctica and trends in mean annual temperature 1979-2000 Trends in sea-ice duration around Antarctica and trends in mean annual temperature 19792000 < -5 -5 to -4 -4 to -3 -3 to -2 -2 to -1 0 to 1 1 to 2 2 to 3 3 to 4 4 to 5 days Source: Connolley, BAS 1985/86 So what does this mean on the ground? 1994/95 Glacier retreat on the Antarctic Peninsula Glacie r retreat on the Antar ctic Penin sula Source: Cook et. al 2005 Ice shelf retreat on the Antarctic Peninsula 5th Mar. 2002 17th Feb. 2002 31st Jan. 2002 1995 Source: NSIDC, BAS W h a t d o e s t h i s m e a n t o l i f e ? S o w h a t i s t h e s i g n i f i c a n c e o f t h e A n t a r c t i c P e n i n s u l a w a r m i n g ? Menu Menu – seallevel rise – life’s a beach, why worry? • Overview of Antarctica • Human fingerprints on the last wilderness • Archive of Planet Earth • Climate change in Antarctica • Sea-level rise – life’s a beach, why worry? • Antarctica and sea-level rise • Getting out there • Science and policy – where next? IPCC IPCC- 2007 “The projections include a contribution due to increased ice flow from Greenland and Antarctica at the rates observed for 1993-2003, but these flow rates could increase or decrease in the future.” Source: IPCCWorking Group I, Summary for Policymakers, 2007 Asymmetry of Sea Level Change Sea Level HIGH LOW Temperature change from present (Celsius) 4 2 0 -2 -4 -6 -8 -10 400 350 300 250 200 WARM COLD 150 100 50 0 Thousands of years before present (present = 1950) THEN NOW Time Source: Bindschadler How many people suffer from coastal flooding today? 10 Million How many people will suffer from coastal flooding by 2080 with no sea level rise? 30 Million If the sea level rise is a conservative 44cm, how many people will suffer? 100 Million Impacts of sea level Sea-level Rise in 500 years? Sea-level rise – 500 years! C i t y o f L o n d o n 1953 flooding of Norfolk and Lincolnshire. Norfolk coast - UK 1953 300 dead, 24,000 homes flooded C a r e f u l h e r e Source: NOAA Sea-level rise - Impacts in the developing world Menu – Antarctica and sealevel rise Menu • Overview of Antarctica • Human fingerprints on the last wilderness • Archive of Planet Earth • Climate change in Antarctica • Sea-level rise – life’s a beach, why worry? • Antarctica and sea-level rise • Getting out there • Science and policy – where next? Antarctica and sea level Bed elevation Antarctica and sea level Source: BEDMAP Antarctica and sea level Areas of Antarctica where ice is below sea level Hydrostatic overburden Source: Unpublished Surface ice-thickness change 1992-2003 Current changes Source: Wingham et al., 2006 Antarctica and sea level Satellite measurement of elevation change • • Amundsen Sea sector 0.043 mm / yr sea level rise (1991-2001) Antarctica and sea level – satellite measurement of elevation change Source: Shepherd, Wingham and Mansley Menu • Overview of Antarctica • Human fingerprints on the last wilderness • Archive of Planet Earth • Climate change in Antarctica • Sea-level rise – life’s a beach, why worry? • Antarctica and sea-level rise • Getting out there • Science and policy – where next? Menu – getting out there G r o u p P i c t u r e B r i t i s h a n d U S F l a g s C a u t i o n t h i s i s c o n j e c t u r e ! ! ! C a u t i o n t h i s i s c o n j e c t u r e ! ! ! a i r p l a n e C a u t i o n t h i s i s c o n j e c t u r e ! ! ! c a m p A r e y o u a l l o w e d t o h a v e f u n d o i n g s c i e n c e ? S u r v e y b y a i r c r a f t West Antarctica 2004/05 mountains West Antarctica 2004/05 Sedimentary basin West Antarctica 2004/05 Lakes beneath 2 km of ice West Antarctica 2004/05 Data pre-2004/05 Data pre-2004/05 Source: Holt et al., Vaughan et al., 2006 West Antarctica 2004/05 2004/05 data 2004/05 data - conjecture Source: Holt et al., Vaughan et al., 2006 West Antarctica 2004/05 Pre2004/05 topograp hy Pre-2004/05 topography Source: Holt et al., Vaughan et al., 2006 West Antarctica 2004/05 New topography New topography Source: Holt et al., Vaughan et al., 2006 C h a n g e m a d e i n o n e s e a s o n Menu • Overview of Antarctica • Human fingerprints on the last wilderness • Archive of Planet Earth • Climate change in Antarctica • Sea-level rise – life’s a beach, why worry? • Antarctica and sea-level rise • Getting out there • Science and policy – where next? Menu – science and policy – where next? Antarctic and the media Antarctic and the media Policy-maker Scientist Science and policy Menu • Overview of Antarctica • Human fingerprints on the last wilderness • Archive of Planet Earth • Climate change in Antarctica • Sea-level rise – life’s a beach, why worry? • Antarctica and sea-level rise • Getting out there • Science and policy – where next? Summary of take-home messages “Our most basic common link is that we all inhabit this planet. We all breathe the same air. We all cherish our children's future.” - John F. Kennedy Kennedy quote Dr. David Vaughan Glaciologist, British Antarctic Survey Dr. Vaughan is the principal investigator for British Antarctic Survey Core Program: Glacial Retreat of Antarctica and Deglaciation of the Earth System (GRADES). The opportunity to define and lead this program was won through open competition. GRADES will employ between 12 and 20 staff and focus on aspects of past and future deglaciation as drivers of change in the Earth System. In 2006 Dr. Vaughan was made Honorary Professor in the School of the Environment and Society, University of Wales, Swansea.