Narragansett Bay Areal Extent of Hypoxia in 2009

October 8, 2009

NOAA CHRP Managers MeetingChristopher Deacutis

Narragansett Bay Estuary Program

URI Coastal, Institute

& Warren Prell & David Murray

Brown Univ.

Minimum D.O.

June 18 ; July15 ; July23

End neap neap strong spring tide

Bottom D.O.

June 18 ; July15 ; July23

Minimum D.O.

Aug 4 ; Aug13 ; Sept. 1

Weak Spring Neap End Neap tide

Bottom D.O.

Aug 4 ; Aug13 ; Sept. 1

Surface D.O.

June 18 ; July15 ; July23

Surface D.O.

Aug 4 ; Aug13 ; Sept. 1

0

10

20

30

40

50

60

70

80

90

100

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 35 37 39 41 43 45 47 49 51 53

% o

f Are

a Su

rvey

ed

Year

Suboxic (<=4.8 mg/L) Hypoxic (<= 2.9 mg/L) Severely Hypoxic (<=1.2 mg/L)

1999 2000 2001 2002 2003 2005 2006 2007 2008 20092004

Narragansett Bay Summer Dissolved Oxygen Spatial Surveys- Botttom DO

• % of Survey Area at various hypoxic levels since 1999 (Total area surveyed ~ 150 km2)

Year

1938

19311948

1955

1968

1972

1982

1984

1986

1998 2003

2006

2009

1938

• Sulfidic waters Greenwich Cove August 18 2009

Fish kill Chepiwanopxet Greenwich Bay August 1,2009

Juv. Winter Flounder

8-1-09

Piscivore Feast

• Good News ! - Ruppia (Widgeon Grass)At Cedar Tree Pt.

Video Break

• Film clips Greenwich BayAugust 14, 2009