A Perfect Storm: The Collision of Tropical Cyclones, Climate Change and Coastal Population Growth. Jeff Donnelly Woods Hole Oceanographic Institution

Transcription

1 A Perfect Storm: The Collision of Tropical Cyclones, Climate Change and Coastal Population Growth Jeff Donnelly Woods Hole Oceanographic Institution

2 Recent Hurricane Trends

3 What Might the Future Hold? N. Atl. Tropical SST N. Atl. Tropical Cyclones N. Hem. Mean Temp From Coumou and Rahmstorf, 2012 Nature Climate Change

4 What Might the Future Hold? N. Atl. Tropical SST N. Atl. Tropical Cyclones N. Hem. Mean Temp Frequency of hurricanes may increase (particularly intense storms) Using IPCC AR4 models Worst Case Best Case Modern

5 What Might the Future Hold? Frequency of hurricanes may increase (particularly intense storms) From Emanuel, 2013 PNAS Using IPCC AR5 models

6 What Might the Future Hold? Rate of sea-level rise will continue to accelerate IPCC AR5

7 Hurricane Sandy billion in damage 148 fatalities

8 Hurricane Sandy SLOSH Simulation

9 Historical Northeast US Hurricanes

10 Historical Northeast US Hurricanes Black = cat 1 and 2 Red cat

11 Historical Northeast US Hurricanes Black = cat 1 and 2 Red cat

12 1821 Hurricane SLOSH Simulation William C. Redfield SLOSH input Track: ~known Translation speed: ~known (~65 km/hr (40 MPH)) Radius of maximum winds:? Intensity:? Though some inferences can be drawn from damage RMW = 46 km Intensity = 51 m/s (115 MPH)

13 1821 Hurricane vs. Sandy Hurricane Sandy 1821 Hurricane

14 1821 Hurricane vs. Sandy in NYC predicted tide surge+tide 1821 Sandy 0:00 4:00 8:00 12:00 16:00 20:00 24:00 Time September 3, Water level relative to mean sea level in 1821 (m) predicted tide surge+tide 0:00 4:00 8:00 12:00 16:00 20:00 24:00 Time October 29, Water level relative to mean sea level in 2012 (m)

15 1821 Hurricane vs. Sandy in NYC 1821 ~4 m of surge predicted tide surge+tide 0:00 4:00 8:00 12:00 16:00 20:00 24:00 Time September 3, Water level relative to mean sea level in 1821 (m) Sandy ~2.75 m of surge predicted tide surge+tide 0:00 4:00 8:00 12:00 16:00 20:00 24:00 Time October 29, Water level relative to mean sea level in 2012 (m)

16 Storm tides in lower Manhattan Maximum Water Level above MSL (m) Hurricanes Winter Storm Date

17 Storm tides in lower Manhattan If 1821 hit at high tide Maximum Water Level above MSL (m) Hurricanes If Sandy hit at low tide Winter Storm Date

18 Hurricane Sandy Storm Tide

19 Hurricane Sandy Storm Tide

20 Hurricane Sandy Storm Tide

21 Hurricane Sandy Storm Tide Long Beach

22 Long Beach Washover Pre Sandy Post Sandy

23 Long Beach Washover

24 What if Sandy hit SE New England?

25 What if Sandy hit SE New England? ~1.4 m of surge at Woods Hole

26 What if Sandy hit SE New England? Woods Hole, MA Monthly highest water Woods Hole tide gauge (above MHW) SLOSH simulation for Woods Hole (above MHW) SLOSH simulation for Woods Hole (above astronomical tide) meters (Carol) Hypothetical SE New England Sandy landfall feet (Donna) 1991 (Bob) Irene Sandy Year Boldt et al. (2010)

27 Why so much damage from Sandy?

28 Why so much damage from Sandy? Future home of Atlantic City (ca. 1833) today

29 Why so much damage from Sandy? Population growth in NJ coastal counties Atlantic Cape May Middlesex Monmouth Ocean Population Year Source: New Jersey Department of Labor and Workforce Development

30 Sea-Level Rise feet From Kemp and Horton, 2013 Journal of Quaternary Science

31 Sedimentary Records of Hurricane Strikes Storm surge from the Great Colonial Hurricane of 1635

32 Sedimentary Records of Hurricane Strikes Overwash sand layer Overwash sand layer WHOI 1 foot Overwash sand layer Overwash sand layer

33 Prehistoric Hurricanes and Climate Age (years CE) Hurricane-induced Sand Layers a - Event deposits Salt Pond, MA Coarse anomaly (%>63µm)

34 Prehistoric Hurricanes and Climate Events/century ʎ = 0.9 (0.002) (0.01) (0.06) (0.2) (0.6) (1) Age (years CE) a - Event deposits Salt Pond, MA Coarse anomaly (%>63µm)

35 Prehistoric Hurricanes and Climate Events/century ʎ = 0.9 (0.002) (0.01) (0.06) (0.2) (0.6) (1) Age (years CE) a - Event deposits Salt Pond, MA 0.01 Basin-wide increases related to warm SST anomaly in deep tropics Coarse anomaly (%>63µm) Increased activity driven by warm SST anomaly off East Coast

36 Landscape Impacts Events/century ʎ = 0.9 (0.002) (0.01) (0.06) (0.2) (0.6) (1) Age (years CE) a - Event deposits Salt Pond, MA 0.01 b - Inlet Formation Outer Banks, NC Coarse anomaly (%>63µm) Cuumulative Events

37 Landscape Impacts 17th Century erosion event Pattagansett Marsh, CT (van de Plassche et al. 2006) Erosive boundary potentially related Great Colonial Hurricane of 1635 Radiocarbon dated samples

38 Summary

39 Summary NJ/NYC were fortunate throughout the 20th century (unfortunately this was a time of unprecedented coastal development)

40 Summary NJ/NYC were fortunate throughout the 20th century (unfortunately this was a time of unprecedented coastal development) Storms of far greater intensity than Hurricane Sandy (and Bob) impacted the area historically (and prehistorically)

41 Summary NJ/NYC were fortunate throughout the 20th century (unfortunately this was a time of unprecedented coastal development) Storms of far greater intensity than Hurricane Sandy (and Bob) impacted the area historically (and prehistorically) Over the last two millennium historically unprecedented intense hurricane activity occurred during intervals of elevated sea surface temperatures

42 Summary The impacts of future hurricane activity will be greatly exacerbated by continuing sea-level rise and coastal population growth, regardless of whether or not we experience significant increases in hurricane landfalls

43 Summary The impacts of future hurricane activity will be greatly exacerbated by continuing sea-level rise and coastal population growth, regardless of whether or not we experience significant increases in hurricane landfalls Intervals of more frequent intense hurricane strikes significantly altered coastal landforms and ecosystems

44 Summary The impacts of future hurricane activity will be greatly exacerbated by continuing sea-level rise and coastal population growth, regardless of whether or not we experience significant increases in hurricane landfalls Intervals of more frequent intense hurricane strikes significantly altered coastal landforms and ecosystems We may see a loss of the protective services these landforms provide if we return to an active hurricane regime

45 Thank you! For more info see:

46 1821 Hurricane Storm Tide in NYC Water level relative to mean sea level in 1821 (ft) Redfield (1831) - Water rose 13 feet (4 m) in lower Manhattan predicted tide surge+tide :00 4:00 8:00 12:00 16:00 20:00 24: Water level relative to mean sea level in 1821 (m) Time September 3, 1821