ACCELERATING SEA ACCELERATING SEA LEVEL RISE: LEVEL RISE: and Florida’s and Florida’s Tenuous Coastal Tenuous Coastal Future Future Harold R. Wanless Harold R. Wanless Department of Geological Department of Geological Sciences Sciences University of Miami University of Miami [email protected]Ecology Club Palm Beach State College Palm Beach State College Boca Raton Boca Raton February 10, 2012 February 10, 2012 http://sedac.ciesin.columbia.edu/gpw/lecz.jsp Mostly < 10 feet
Power Point delivered to the LCG Ecology Club at Palm Beach State College on February 10, 2012 by Dr. Harold Wanless Professor and chair at the University of Miami
This document is posted to help you gain knowledge. Please leave a comment to let me know what you think about it! Share it to your friends and learn new things together.
Ecology ClubPalm Beach State CollegePalm Beach State College
Boca RatonBoca Raton
February 10, 2012February 10, 2012
http://sedac.ciesin.columbia.edu/gpw/lecz.jsp
Mostly < 10 feet
HUMAN-INDUCED GLOBAL WARMING IS REAL.HUMAN-INDUCED GLOBAL WARMING IS REAL.
+1 ppm/yr
+2 ppm/yr
AND IS ACCELERATING!AND IS ACCELERATING!
GLOBAL MEAN SEA LEVEL
Present global rise= 30 cm/century
= S. Florida rate
1930MOST OF THIS RISE IS
BECAUSE OF THERMAL EXPANSION
OF THE OCEAN
8-fold in
crease
over p
revious 2
,000 years
1930 SAME AS GLOBAL BUT WITH MORE VARIABILITY
8-fold in
crease
over p
revious 2
,000 yearsKey West Sea Level
1997El Nino
South Florida sea level rise
= 30 cm/century
= global rate
Global sea level rise (based on tide gauge and satellite data) has been following the highest end of the 2001 IPCC sea level projection.
LOW
HIGH
MEDIUM
Satellite Altim
etry
Satellite Altim
etrySea level rise is running at the high end of predictions
– and is accelerating!
Rapid atmospheric and ocean warming in Rapid atmospheric and ocean warming in the Arctic and Antarctic is now driving the Arctic and Antarctic is now driving
accelerating ice melt and sea level rise.accelerating ice melt and sea level rise.
ACCELERATING ICE MASS LOSS ON GREENLAND ACCELERATING ICE MASS LOSS ON GREENLAND AND ANTARCTICA FROM THE GRACE SATELLITESAND ANTARCTICA FROM THE GRACE SATELLITES
Science, October 6, 2009, p.217.
Rate of mass loss has more than doubled over past 7 years on both Greenland and Antarctica.Is now an annual 17% acceleration in melt rate and a 5% acceleration in the contribution to rise in sea level.
an ice loss acceleration of -30 km3/yr/yr
Antarctica Ice Loss
Velicogna, 2009. Geophysical Research Letters
Accelerated Accelerated ice melt on both ice melt on both Greenland and Greenland and
Antarctica began Antarctica began in mid 1990s and in mid 1990s and
now is the now is the dominant dominant
contributor to sea contributor to sea level rise.level rise.
River on Greenland Ice Sheet flowing down moulin to lubricate base.
There is no uncertainty that There is no uncertainty that global sea level is rising at an global sea level is rising at an accelerating rate because of accelerating rate because of
human induced global warming human induced global warming of the atmosphere and ocean.of the atmosphere and ocean.
The only uncertainty is how fast The only uncertainty is how fast and how soon will it severely and how soon will it severely
impact us.impact us.
Scientists on the Miami-Dade County Scientists on the Miami-Dade County Climate Change Advisory Task Force:Climate Change Advisory Task Force:
““With what is happening in the Arctic and Greenland, With what is happening in the Arctic and Greenland, [there will be] a likely sea level rise of [there will be] a likely sea level rise of at least 1.5 feet 1.5 feet in the coming 50 yearsin the coming 50 years andand a totala total of of at leastat least 3-5 feet 3-5 feet by the end of the centuryby the end of the century, possibly significantly , possibly significantly more. Spring high tides would be at +7 to +9 feet. more. Spring high tides would be at +7 to +9 feet.
““This does not take into account the This does not take into account the possibility of a possibility of a catastrophically rapid melt of land-bound ice from catastrophically rapid melt of land-bound ice from GreenlandGreenland, and it makes no assumptions about , and it makes no assumptions about Antarctica.”Antarctica.”
““The projected The projected rises will just be the beginning rises will just be the beginning because of further significant releases from Greenland because of further significant releases from Greenland and possibly Antarctica.”and possibly Antarctica.”
(September 20, 2007)
The U.S. Army Corps of Engineers is now required to The U.S. Army Corps of Engineers is now required to incorporate likely sea level rise into all planning; this is also incorporate likely sea level rise into all planning; this is also
used by the Southeast Florida Regional Planning Councilused by the Southeast Florida Regional Planning Council
With continued melt from the Ice Sheets at the current With continued melt from the Ice Sheets at the current acceleration, and conservative but realistic projections for acceleration, and conservative but realistic projections for
glacial ice melt and further expansion of the oceans through glacial ice melt and further expansion of the oceans through warming, sea level will be at least 4.5 feet higher ( ) by the warming, sea level will be at least 4.5 feet higher ( ) by the
end of the century – likely much more.end of the century – likely much more.
If at + 5 feet at 2100, sea level will be rising at 1 foot per
decade – and accelerating!
North Pole web cam – August 25, 2007North Pole web cam – August 25, 2007
Ice reflects nearly all incoming solar radiation back into the air and space. Open water absorbs over 90% of incoming solar radiation
Arctic sea ice has reached it Arctic sea ice has reached it minimum for the year and is minimum for the year and is essentially tied with 2007 for essentially tied with 2007 for record low areal extent – but the record low areal extent – but the ice is significantly thinner than in ice is significantly thinner than in 2007, so volume is dramatically 2007, so volume is dramatically less. less.
2011 Arctic Sea Ice Extent
Median 1979-2000
ARCTIC SEA ICE EXTENT
9/9/2011 AREAS 9/9/2011 AREAS WITH > 15% ICEWITH > 15% ICE
2011 was an extraordinary melt year because the 2011 was an extraordinary melt year because the Arctic weather was normal. In 2007 weather was Arctic weather was normal. In 2007 weather was anomalous, forcing high melt.anomalous, forcing high melt.
Arctic sea ice is now too thin to hold up under Arctic sea ice is now too thin to hold up under normal conditions.normal conditions.
It is now likely that the Arctic will have ice free It is now likely that the Arctic will have ice free summers within 15 years and possibly within 2.summers within 15 years and possibly within 2.
As the Arctic goes from white ice to dark ocean in As the Arctic goes from white ice to dark ocean in the summer, the Arctic Ocean is rapidly adsorbing the summer, the Arctic Ocean is rapidly adsorbing heat from the sun.heat from the sun.
Less and less thick (old) ice each year.Less and less thick (old) ice each year.
Tundra and permafrost rim the Arctic OceanTundra and permafrost rim the Arctic Ocean
• Tundra and permafrost beneath is frozen ground 150-2,000 feet thick.
• Huge amounts of organics are frozen in the permafrost.
• 80% of tundra is within 100 km of Arctic Sea Ice.
• 20% of tundra has been lost since the 1980s.
• 3-5 meters of permafrost are expected to melt in the coming 100 years (Ted Schuur, University of Florida).
• Organic decay from melting the upper 3 meters of permafrost will release as much CO2 as is presently in the atmosphere.
Methane HydratesMethane Hydrates
An ice cage with a methane inside.
Occurs both on the sea floor and in permafrost.
Arctic – Shallow shelf and on land
Tropical > 2,000 meters
Reinforcing feedbacks Reinforcing feedbacks in the Arctic and Greenland in the Arctic and Greenland
make future rapid warming and make future rapid warming and accelerating sea level rise accelerating sea level rise inevitable and unstoppable.inevitable and unstoppable.
Reinforcing feedbacks: Arctic OceanReinforcing feedbacks: Arctic Ocean1.1. Persistent warming from Persistent warming from
atmosphere.atmosphere.2.2. More open waterMore open water3.3. More heat adsorptionMore heat adsorption4.4. More melting More melting 5.5. Warming of adjacent tundra and Warming of adjacent tundra and
northern Greenlandnorthern Greenland
6.6. Accelerated release of COAccelerated release of CO22, CH, CH44, , and ice meltand ice melt
Reinforcing feedbacks: GreenlandReinforcing feedbacks: Greenland1.1. Surface melt areas adsorb more Surface melt areas adsorb more
heat.heat.2.2. Melt water lubricates base of ice Melt water lubricates base of ice
sheetsheet3.3. Rapid loss to oceanRapid loss to ocean4.4. Lowering of ice sheet elevation Lowering of ice sheet elevation 5.5. Further warming and Further warming and
destabilization. destabilization.
South Florida South Florida 19951995
CR
TP
CS
C
South Florida South Florida ~2060~2060
+2 foot rise (mhhw = +4.5’ above 1929 MSL)
CR
TP
CS
C
1-2’ versus 3-5’ – All the difference1-2’ versus 3-5’ – All the difference A 1-2 foot rise this century – A 1-2 foot rise this century –
Miami, barrier islands and upper Keys are still Miami, barrier islands and upper Keys are still sort of inhabitable; sort of inhabitable;
probably worth throwing up extensive probably worth throwing up extensive defenses; defenses;
and just maybe will get hold of global warming and just maybe will get hold of global warming problem before all is lost.problem before all is lost.
Every county and city urgently needs accurate Every county and city urgently needs accurate and detailed elevation maps from which to and detailed elevation maps from which to
assess future drainage and infrastructure risk.assess future drainage and infrastructure risk.
In SE Florida, a 50 cm (20 inch) sea level rise will make In SE Florida, a 50 cm (20 inch) sea level rise will make 80% of our coastal water control structures useless. 80% of our coastal water control structures useless.
1-2’ versus 3-5’ – All the difference1-2’ versus 3-5’ – All the difference
3-5 foot rise this century – 3-5 foot rise this century – All barrier islands abandoned; All barrier islands abandoned; Miami-Dade & Broward diminished and risky Miami-Dade & Broward diminished and risky
place to live - including all of the Florida Keys; place to live - including all of the Florida Keys; increased pollution risk from eroding dumps;increased pollution risk from eroding dumps; sea level rising at 0.6 to1 foot per decade.sea level rising at 0.6 to1 foot per decade.
South Florida South Florida ~2085~2085
+4 foot rise (mhhw = +6.5’ above 1929 MSL)
CR
TP
CS
C
South Florida South Florida ~2102~2102
+5 foot rise (mhhw = +7.5’ above 1929 MSL)
CR
TP
CS
C
STORM SURGESSTORM SURGESFROM ALL SIDESFROM ALL SIDES
South Florida South Florida ~2112~2112
+6 foot rise (mhhw = +8.5’ above 1929 MSL)
CR
TP
CS
C
?? EMBAYMENTZONE OF
HIGHER TIDES ??
ON TOP OF THIS SEA LEVEL RISEON TOP OF THIS SEA LEVEL RISE WILL BEWILL BE HIGHER TIDES AND STORM SURGESHIGHER TIDES AND STORM SURGES
Bolivar Peninsula, TexasBolivar Peninsula, Texas Hurricane Ike, Category 2, September 2008Hurricane Ike, Category 2, September 2008
from PPT by William B Potterfrom PPT by William B Potter
This is high tide in the 1700 block of North Bayshore Dr., Miami FL. Unfortunately, this flooding is not associated with storm surge or any other exceptional tidal or weather event. It has become the regular twice a day occurrence of the tide.
from Tim O. Walker
SEPT 2008SEPT 2008
By 2050, By 2050,
Earth is projected to haveEarth is projected to have
Miami is the most vulnerable Miami is the most vulnerable
- But may not be the first.- But may not be the first.
Regional influences in SLRRegional influences in SLR
Regional subsidence or uplift of land.Regional subsidence or uplift of land. Post glacial rebound, collapse of peripheral Post glacial rebound, collapse of peripheral
bulge, tectonic, from withdrawal of fluids.bulge, tectonic, from withdrawal of fluids. Changing speed or pattern of currents.Changing speed or pattern of currents. Redistribution of balance of mass between Redistribution of balance of mass between
water and land on the planet, affecting water and land on the planet, affecting Earth's rotation (causing water to build up Earth's rotation (causing water to build up along the North American coasts and in along the North American coasts and in the Indian Ocean).the Indian Ocean).
NEW YORKSouth Manhattan
Filled Land
Filled Marsh
Filled Lakes
MOST VULNERABLELOW-LYING LAND
Presently has relative Sea-level rise of~55 cm /century
Most coastal fill is less than 2 meters above sea level.
SHANGHAISHANGHAI
Population 16 million, Population 16 million, Average elevation 4 meters,Average elevation 4 meters, On the Yangtze River delta,On the Yangtze River delta, A 6.9 meter dyke presently A 6.9 meter dyke presently
protects portions of the city protects portions of the city from typhoons surges,from typhoons surges,
9 subways9 subways but -but -
Shanghai is rapidly subsiding from groundwater Shanghai is rapidly subsiding from groundwater withdrawal (current rates are 1-2 meters/century)!withdrawal (current rates are 1-2 meters/century)!
from: Liu, Luo, Chen, Huang and Ding, 2008
10 years
15 c
m
Subsidence rates for Shanghai (mm/yr)
MUMBAI, INDIAMUMBAI, INDIA
Filled from Sea
Filled Marsh
Sandy Coastal Strand
MOST VULNERABLELOW-LYING LAND
Low Land and Drained Marsh
Rocky Upland
-15 million people.-One fourth of area is at or below sea level.-Current sea level rise is ~20 cm / century
+6 ft
+5 ft+4 ft
MUMBAIMUMBAI22 million (really 30+)22 million (really 30+)
+3 ft
3 million passengers a day – 4 feet above sea level3 million passengers a day – 4 feet above sea level
The problem of a philosophy of The problem of a philosophy of permanence of place & environmentpermanence of place & environment
We just can’t imaging losing where we are.We just can’t imaging losing where we are.
Makes us want to defend!! Makes us want to defend!!
IMPORTANTLY,IMPORTANTLY, FLORIDA IS UNDERLAIN BY FLORIDA IS UNDERLAIN BY
POROUS LIMESTONE AND SAND POROUS LIMESTONE AND SAND
We cannot We cannot build dikes build dikes to keep out to keep out
rising water.rising water.
BLUE IS POROSITY
Thin section of Miami Limestone from Dr. Donald McNeill
Areas > 5 feet above mean sea level
Key Biscayne – Key Biscayne – Potentially emergent areas Potentially emergent areas at MHHW with a +2.5 foot at MHHW with a +2.5 foot sea level risesea level rise
Elevations based on 1962 USGS topographic map
Will actually
look more like
this
The problem is The problem is that sandy that sandy
barrier islands barrier islands will try to move will try to move
landward –landward –
or if the rise is too or if the rise is too fast, it will just be fast, it will just be over ridden and over ridden and
abandoned.abandoned.
Cape Romano, November 18, 2003Cape Romano, November 18, 2003
With a 4-5 foot rise in sea level, With a 4-5 foot rise in sea level, essentially all sandy barrier islands on essentially all sandy barrier islands on
Earth will be abandoned - rapidly Earth will be abandoned - rapidly migrating landward or being overridden.migrating landward or being overridden.
Tidal inlets will become more numerous, and many lagoons will become basically open to the sea
MIAMI-DADE COUNTY LiDAR MAPSMIAMI-DADE COUNTY LiDAR MAPS
PRESENTTOPOGRAPHY
+0.6 m (+2 ft)
Sea Level Rise
100% land area
72% land remains
MHW MHW
TURKEY POINT
T T
D DD D
D DD D
D DMIA MIA
from P. Harlem, 2010
~2060
MIAMI-DADE COUNTY LiDAR MAPSMIAMI-DADE COUNTY LiDAR MAPS
+1.8 m (+6 ft)
Sea Level Rise
+1.2 m (+4 ft)
Sea Level Rise
44% land remains73% of that is less
than 2 feet above sea level
62% land remains
MHW MHW
T T
D DD D
D DD D
D DMIA MIA
from P. Harlem, 2010
~2090 ~2112
MIAMI-DADE COUNTY LiDAR MAPSMIAMI-DADE COUNTY LiDAR MAPS
+2.4 m (+8 ft)
Sea Level Rise
+3.0 m (+10 ft)
Sea Level Rise
9% land remains
12% land remains
MHW MHW
T T
D DD D
D DD D
D DMIA MIA
from P. Harlem, 2010
~2120 ~2135
““The warming we're on The warming we're on track to do now is track to do now is more than enough to more than enough to commit us to last-commit us to last-interglacial levels of interglacial levels of sea-level rise.” sea-level rise.”
(Kopp, Nature, 2009).(Kopp, Nature, 2009).
Now the bad news -Now the bad news -
Pre-industrial
Today
From Hansen, 2009, p. 153
?
We have seriously increased the warming stressors. We must expect ice melt and sea level to respond as it
has in the past.
If nothing is done to If nothing is done to slow greenhouse gas slow greenhouse gas
emissions,emissions,
By 2100By 2100
COCO22 concentrations will concentrations will
likely be more than 700 ppmlikely be more than 700 ppm
Global average Global average temperatures projected to temperatures projected to
increase between 2.5–10.4°Fincrease between 2.5–10.4°F
Last time carbon dioxide Last time carbon dioxide was so high, se level was was so high, se level was
over 100 feet higher.over 100 feet higher.
2100
Source: OSTP
Climate, Ice and Sea Level Do Not Climate, Ice and Sea Level Do Not Respond Gradually to stressesRespond Gradually to stresses
When stressed and destabilized, climate, When stressed and destabilized, climate, polar ice and sea level will, at some point, polar ice and sea level will, at some point, reach a tipping point and undergo rapid reach a tipping point and undergo rapid change towards a new state.change towards a new state.
IPCC and other climate and sea level IPCC and other climate and sea level forecasts assume gradual linear forecasts assume gradual linear responses and changes - not sudden responses and changes - not sudden tipping points, switches to new states, tipping points, switches to new states, rapidly reinforcing feedbacks, rapid ice rapidly reinforcing feedbacks, rapid ice melts and rapid sea level rises.melts and rapid sea level rises.
FLORIDA THROUGH TIMEFLORIDA THROUGH TIME
120,000 years ago 18,000 years ago Today120,000 years ago 18,000 years ago Today
+ 6 meters+ 6 meters - 120 meters - 120 meters
100 miles
~ ½ from Greenland~ ½ from Antarctica
How did this sea How did this sea level rise occur?level rise occur?
PROJECTED SEA LEVEL RISE RATE BY 2100
Based on Fairbanks, 1989
SLIDE COURTESY OF ROB THIELER, USGS
PROJECTED SEA LEVEL RISE RATE BY 2100
Based on Fairbanks, 1989
SLIDE COURTESY OF ROB THIELER, USGS
LOCKER et alLOCKER ET AL, 1996
-Florida Straits
-80 m
-71 m-65 m
SEA LEVEL STILL STANDS
ANDRAPID RISES
Recent research shows that relative sea level rise Recent research shows that relative sea level rise is not a simple curve but one with significant is not a simple curve but one with significant
stalls and rapid rises.stalls and rapid rises.
As sea level was first advancing out of the As sea level was first advancing out of the last ice age, it rose in 6-10 meter steps 200-last ice age, it rose in 6-10 meter steps 200-500 years apart, each still stand leaving a 500 years apart, each still stand leaving a
Pulley Ridge, a deep Pulley Ridge, a deep coral reef capping a coral reef capping a
drowned barrier island drowned barrier island formed during two sea formed during two sea
level still stands. level still stands.
From: Jarrett et al, Marine Geology, 2005
-80m-71m
LOCKER ET AL, 1996 -Florida Straits
JARRETT ET AL, 2005- SW Florida Shelf
et al
ANDERSON ET AL, 2004 - Texas Shelf
RODRIGUEZ ET AL,2000 - Texas Shelf
-19 m
-27 m
-38 m
SEA LEVEL STILL STANDS
ANDRAPID RISES
LOCKER ET AL, 1996 -Florida Straits
JARRETT ET AL, 2005- SW Florida Shelf
et al
ANDERSON ET AL, 2004 - Texas Shelf
RODRIGUEZ ET AL,2000 - Texas Shelf
-19 m
-27 m
-38 m
Steps of rapid sea level riseSteps of rapid sea level riseTexas ShelfTexas Shelf
TT
-19m-27m
-38m+11m
+8m
Sand Tidal Delta, Sand Tidal Delta, built to intertidalbuilt to intertidal John Anderson,John Anderson,
Rice UniversityRice University
et alLOCKER ET AL, 1996
-Florida StraitsJARRETT ET AL, 2005
- SW Florida Shelf
ANDERSON ET AL, 2004 - Texas Shelf
RODRIGUEZ ET AL,2000 - Texas Shelf
-16,-15,-14,-13 m-9, -6 mMILLIKEN ET AL,
2008 – Texas Shelf
SEA LEVEL STILL STANDS
ANDRAPID RISES
et alLOCKER ET AL, 1996
-Florida StraitsJARRETT ET AL, 2005
- SW Florida Shelf
ANDERSON ET AL, 2004 - Texas Shelf
RODRIGUEZ ET AL,2000 - Texas Shelf
MILLIKEN ET AL,2008 – Texas Shelf
, *D & W, 1991GELSANLITER, 1996
*D & W = DOMINGUEZ AND WANLESS, 1991 - Florida and Brazil
SEA LEVEL STILL STANDS
ANDRAPID RISES -2.6, -1.8, -1.2 -2.6, -1.8, -1.2
mm
11 22 33
44
11
443322
Florida Bay Florida Bay was inundated was inundated
during two during two pulses of sea pulses of sea
level rise level rise between 4,500 between 4,500 and 3,200 ybp.and 3,200 ybp.
4,000 ybp4,000 ybpcoastlinecoastline
3,200 ybp3,200 ybpcoastlinecoastline
CAPE SABLECAPE SABLE
THE MANG
ROVE CO
AST
THE MANG
ROVE CO
AST
GOPHERGOPHER CREEKCREEK
Florida Bay
Eve
rgla
desCO
ASTLINE 3,200 YPB
COASTLINE 3,200 YPB
Gelsanliter, 1996Gelsanliter, 1996
Adapted from Adapted from Dominguez and Wanless, 1991Dominguez and Wanless, 1991
A small, rapid rise 2,500-2,400 ybp; then a 400 A small, rapid rise 2,500-2,400 ybp; then a 400 year period of intensive sediment erosion and year period of intensive sediment erosion and
recycling.recycling.
1 meter1 meter
Gelsanliter, 1996Gelsanliter, 1996
LASTLAST
CO
AS
TA
L
CO
AS
TA
L E
RO
SIO
N a
nd
ER
OS
ION
and
IN
UN
DA
TIO
N
INU
ND
AT
ION
COASTAL COASTAL STABILIZATIONSTABILIZATION
& SED RECYCLING& SED RECYCLING
CAN THERE BE SIGNIFICANT RAPID CAN THERE BE SIGNIFICANT RAPID
SEA LEVEL PULSES IN THE SEA LEVEL PULSES IN THE FUTURE? FUTURE?
YES.YES.
A. DURING THE LAST INTERGLACIAL, A. DURING THE LAST INTERGLACIAL, ABOUT 130,000-120,000 YEARS AGO, SEA ABOUT 130,000-120,000 YEARS AGO, SEA
LEVEL ROSE RAPIDLY PAST PRESENT SEA LEVEL ROSE RAPIDLY PAST PRESENT SEA LEVEL TO ABOUT + 7 METERS AT A RATE LEVEL TO ABOUT + 7 METERS AT A RATE THAT COASTAL DEPOSITS DID NOT FORM.THAT COASTAL DEPOSITS DID NOT FORM.
SHELF MARGIN – SHELF MARGIN – TOO DEEP FOR REEF GROWTHTOO DEEP FOR REEF GROWTH
PLEISTOCENE 130-120,000 YEAR OLD
REEF FORMED WHERE SUBSTRATE WAS < 13m.
DEPTH OF REEF INITIATION
PRESENT SEA LEVEL
125,000 ybp SEA LEVEL
+4 m
-9 m
B. Evidence for brief 82,000 ybp highstand at +2.5m B. Evidence for brief 82,000 ybp highstand at +2.5m
ABOUT 84,000 YERS AGO ABOUT 84,000 YERS AGO SEA LEVEL ROSE SEA LEVEL ROSE FROM ABOUT -30 FROM ABOUT -30 METERS TO +2.5 METERS TO +2.5 METERS AT AN METERS AT AN AVERAGE RATE OF ~2 AVERAGE RATE OF ~2 METERS/CENTURY, METERS/CENTURY, LEAVING NO COASTAL LEAVING NO COASTAL DEPOSITS BELOW +2.5 DEPOSITS BELOW +2.5 METERSMETERS
(from (from Dorale, J.A., Dorale, J.A., et al., 2010, et al., 2010, Science v. 327, p. 860.)Science v. 327, p. 860.)70 85 100 115 130
Age (ka)
It is time to begin the It is time to begin the consideration of pulses of consideration of pulses of rapid sea level rise in the 1-10 rapid sea level rise in the 1-10 meter range in the near future.meter range in the near future.
Leading to 10-30 m (33-100 ft)Leading to 10-30 m (33-100 ft)sea level rise from multiple sea level rise from multiple pulses of sea level rise.pulses of sea level rise.
With the CO2 levels now reached, the oceanic warming achieved, and the initiation of melt on both Ice Sheets -
Elevations greater than 150’
Recommend quick Recommend quick planning and planning and implementation for putting implementation for putting things too important to things too important to loose and too valuable to loose and too valuable to be disrupted be disrupted At greater than 165 feet At greater than 165 feet
(>50 meters) elevation and(>50 meters) elevation and
In areas that will not be in In areas that will not be in
the chaos of rapid the chaos of rapid relocation.relocation.
Elevations greater than 150’
At the beginning of the Century, we watched At the beginning of the Century, we watched rapid melting of Greenland’s marginrapid melting of Greenland’s margin
2001 20032002
100 mi
From atmospheric warming of the ArcticFrom atmospheric warming of the Arctic
Lakes, rivers and moulins (openings through which water pours down through the ice) in the Greenland Ice Sheet
Meltwater lake and streams on the Greenland Ice Sheet near 68ºN at Meltwater lake and streams on the Greenland Ice Sheet near 68ºN at 1000 meters altitude. Photo by Ian Joughin. From Realclimate.org1000 meters altitude. Photo by Ian Joughin. From Realclimate.org
Each year being more and moving higher.Each year being more and moving higher.
MOULINSMOULINSLike karst in limestonesLike karst in limestones
Water lubricates base of ice sheet and results in sliding, fracturing and weakening of the ice sheet.
The Jacobshavn Isbreen (5 km wide and 1.5 km deep) is now The Jacobshavn Isbreen (5 km wide and 1.5 km deep) is now moving at 15km a year into the sea, although in surges it moving at 15km a year into the sea, although in surges it moves even faster. ‘One surge moved 5 km in 90 minutes - an moves even faster. ‘One surge moved 5 km in 90 minutes - an extraordinary event. It’s exuding like toothpaste.’extraordinary event. It’s exuding like toothpaste.’
"Five years ago we made models predicting how much "Five years ago we made models predicting how much ice would melt and when. "Five years later we are ice would melt and when. "Five years later we are already at the levels predicted for 2040, in a year's already at the levels predicted for 2040, in a year's time we'll be at 2050." time we'll be at 2050."
(Veli Albert Kallio, Finnish polar/ice scientist, September 8, 2007)(Veli Albert Kallio, Finnish polar/ice scientist, September 8, 2007)
ACCELERATING ICE MASS LOSS ON GREENLAND ACCELERATING ICE MASS LOSS ON GREENLAND AND ANTARCTICA FROM THE GRACE SATELLITESAND ANTARCTICA FROM THE GRACE SATELLITES
Science, October 6, 2009, p.217.
Rate of mass loss more than doubled on both Greenland and Antarctica between 2002 and 2009.Is now an annual 17% acceleration in melt rate and a 5% acceleration in the contribution to rise in sea level.
an ice loss acceleration of -30 km3/yr/yr
Antarctica Ice Loss
Velicogna, 2009. Geophysical Research Letters
M. Nettles and G. Ekstrom, 2010. Annu. Rev. Earth Planet. Sci. 2010.38:467-491. doi: 10.1146/annurev-earth-040809-152414
Map of Greenland showing locations of 184 glacial earthquakes for the period 1993–2005. Note the tight clustering of
earthquake epicenters near major outlet glaciers.
Antarctic teleseismic detections that are likely to correspond to Antarctic teleseismic detections that are likely to correspond to
glacial earthquakes.glacial earthquakes.
M. Nettles and G. Ekstrom, 2010. Annu. Rev. Earth Planet. Sci. 2010.38:467-491. doi: 10.1146/annurev-earth-040809-152414
Collapsing front Collapsing front of glacial of glacial
outlets produce outlets produce seismic events.seismic events.
700 m700 m
70 m
Helheim Glacier, Greenland
M. Nettles and G. Ekstrom, 2010. Annu. Rev. Earth Planet. Sci. 2010.38:467-491. doi: 10.1146/annurev-earth-040809-152414
ICE DISCHARGE THROUGH OUTLET GLACIERS HAS ICE DISCHARGE THROUGH OUTLET GLACIERS HAS DRMATICALLY INCREASED – BECAUSE OF WARM OCEAN DRMATICALLY INCREASED – BECAUSE OF WARM OCEAN WATERS MOVING IN BELOWWATERS MOVING IN BELOW
The Jacobshavn Isbreen in western Greenland (5 km wide and The Jacobshavn Isbreen in western Greenland (5 km wide and 1.5 km deep) is now moving at more 15km a year into the sea, 1.5 km deep) is now moving at more 15km a year into the sea, although in surges it moves even faster.although in surges it moves even faster.
We now know that warm waters moving under We now know that warm waters moving under the outlets are driving the accelerated melt.the outlets are driving the accelerated melt.
Jacobshavn Isbreen I in Ilulissat, Vestgrønland (Greenland); Photograph by Dirk JenrichJacobshavn Isbreen I in Ilulissat, Vestgrønland (Greenland); Photograph by Dirk Jenrich
20092009- - Pine Island Glacier, a major outlet for the West Antarctic Pine Island Glacier, a major outlet for the West Antarctic Ice Sheet (WAIS), is melting at a rate 4 times faster than just a Ice Sheet (WAIS), is melting at a rate 4 times faster than just a decade ago – because of warming waters. decade ago – because of warming waters.
It is thinning at 16 m per year – 90 m in the past decade. It is thinning at 16 m per year – 90 m in the past decade.
A. Shepard, University of
Leeds, August 2009.
WAIS
Pine Island Glacier
acquired October 16 - November 9, 2009
PINE ISLAND GLACIER - Major outlet for West Antarctic Ice Sheet
In October 2009, a series of flights over Antarctica led to the discovery of a hidden feature beneath a floating ice shelf. Scientists participating in NASA’s Operation IceBridge mapped the water depth and seafloor topography beneath Pine Island Glacier and found a deepwater channel—a likely pathway for warm water to reach the glacier’s underbelly and melt it from below. The top image above shows the bathymetry beneath Pine Island Glacier. The deepest regions (navy blue) are about 1,200 meters (3,900 feet) deep while elevated seamounts and shoals (pale blue to white) are mostly 200 meters (650 feet) below sea level. The lower image shows Pine Island Glacier and the surrounding solid land in Antarctica as they appear from space in a Landsat Image Mosaic of Antarctica. The black, jagged outline in both images shows the “grounding line,” the point where the glacier is attached to the bedrock along the coast.
Estuarine circulation now promoting Estuarine circulation now promoting rapid melting beneath ice.rapid melting beneath ice.
Warm denser ocean water flows inWarm denser ocean water flows in
Cooled less dense melt water flows outCooled less dense melt water flows out Melting and
Melting and
mixing
mixing
60 kilometers
Can melt much of the West Antarctic Ice Sheet Can melt much of the West Antarctic Ice Sheet from below – and have in the past.from below – and have in the past.
= was open seaway during last interglacial (when sea level was 20’ higher than today)
= Pine Island glacier outlet of West Antarctic Ice Sheet
Ronne-Fincher Ice Shelf
RossIce Shelf
Pine Island Glacier
Earth has a close Earth has a close to catastrophic to catastrophic evolution of its evolution of its
coastal and low-coastal and low-lying environments, lying environments,
habitats, habitats, infrastructure and infrastructure and
resources resources underway.underway.
• We probable will have to deal with the beginning several feet of the coming sea level rise.
• If humanity If humanity quickly gets its act quickly gets its act together, we may together, we may be able to prevent be able to prevent this.this.
• If we do not, south Florida If we do not, south Florida will most certainly look like this will most certainly look like this within a couple of centuries, within a couple of centuries, possibly within this century.possibly within this century.
+4 ft
+20 ft
+6 ft
What level of uncertainty accompanies What level of uncertainty accompanies the models, predictions and empirical the models, predictions and empirical
measurements upon which these measurements upon which these estimates are based?estimates are based?
Minimum is quite certain and should be accelerating. Minimum is quite certain and should be accelerating. Consensus that there will be accelerating SLR well Consensus that there will be accelerating SLR well
beyond end of century unless we rapidly reduce GHG beyond end of century unless we rapidly reduce GHG levels in atmosphere.levels in atmosphere. Not certain when there will be rapid pulses of ice Not certain when there will be rapid pulses of ice
release and melt and sea level rise –BUT IT WILL release and melt and sea level rise –BUT IT WILL HAPPEN.HAPPEN.
What can we do?What can we do? Most critically, we need to get off the CO2-producing Most critically, we need to get off the CO2-producing
addiction. addiction.
+1 ppm/yr
+2 ppm/yr
Leading climatologist, Dr. James Hansen, says we Leading climatologist, Dr. James Hansen, says we quicklquickly y need to reduce atmospheric CO2 to 325-350 ppm.need to reduce atmospheric CO2 to 325-350 ppm.
350 ppm
Presently 387 ppm and rising about 2.5 ppm / year
325 ppm
We must stop warming.We must stop warming.
This probably will not slow the first 3-5 feet of sea level rise, but This probably will not slow the first 3-5 feet of sea level rise, but may be a step for limiting a catastrophic greater rise. may be a step for limiting a catastrophic greater rise.
+1 ppm/yr
+2 ppm/yr
Lowering atmospheric CO2 will slow the heat Lowering atmospheric CO2 will slow the heat imbalance between the atmosphere and the ocean.imbalance between the atmosphere and the ocean.
350 ppm
325 ppm
The United States is still the The United States is still the leading cause of global warming.leading cause of global warming.
We must take the lead in -We must take the lead in - Drastically reducing our greenhouse gas Drastically reducing our greenhouse gas
and fine particulate soot production and and fine particulate soot production and release.release.
Rapid development and implementation Rapid development and implementation of truly clean energy sources.of truly clean energy sources.
Removing CORemoving CO22 from the atmosphere. from the atmosphere. Then, we can take the leadership that the Then, we can take the leadership that the
world will follow.world will follow.
In a time of rapid sea level In a time of rapid sea level rise, we must workrise, we must work
responsibly to reduce -responsibly to reduce -
• economic risk in coastal economic risk in coastal development,development,
• risk to human life and risk to human life and property,property,
• environmental environmental degradation associated degradation associated with challenging an with challenging an advancing ocean,advancing ocean,
• the level of greenhouse the level of greenhouse gasses in the gasses in the atmosphere. atmosphere.
It is curiously inconvenient and a bit comic now – It is curiously inconvenient and a bit comic now – but not when you visualize the remainder of the but not when you visualize the remainder of the
century.century.
Venice, Italy
High tide in the 1700 block of North Bayshore Dr., Miami FL. Unfortunately, this flooding is not associated with storm surge or any other exceptional tidal or weather event.
SEPT 2008SEPT 2008
You have front row seatsYou have front row seatsright here in Florida – for a while.right here in Florida – for a while.
Miami-Dade
Present topography as shown with LiDAR elevation data from P. Harlem, 2011
Miami-Dade
Inundation from 1 ft. Sea Level Risefrom P. Harlem, 2011
Miami-Dade
Inundation from 2 ft. Sea Level Risefrom P. Harlem, 2011
Miami-Dade
Inundation from 3 ft. Sea Level Risefrom P. Harlem, 2011
Miami-Dade
Inundation from 4 ft. Sea Level Risefrom P. Harlem, 2011
Miami-Dade
Inundation from 5 ft. Sea Level Risefrom P. Harlem, 2011
Miami-Dade
Inundation from 6 ft. Sea Level Risefrom P. Harlem, 2011
Miami-Dade
Inundation from 7 ft. Sea Level Risefrom P. Harlem, 2011
Miami-Dade
Inundation from 8 ft. Sea Level Risefrom P. Harlem, 2011
Miami-Dade
Inundation from 9 ft. Sea Level Risefrom P. Harlem, 2011
Miami-Dade
Inundation from 10 ft. Sea Level Risefrom P. Harlem, 2011
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