Progress in WQSTM Climate Change Analyses

Richard Tian and CBPO modeling team

Modeling Quarterly Review04/02/2019Annapolis

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Outline• Sea level rise

• Heat flux

• Temperature parameter values

• Nutrient loading

• Preliminary results for 2025

β1 = 5.203 mm/yrβ2 = 0.12 mm/yr2

(with 2018 data. Boon, Mitchel and others)

https://www.vims.edu/research/products/slrc/localities/norfolkva/index.php

Quadratic function projection, Norfolk

R2=0.52

R2=0.51

y = -2E-11x + 1E-06R² = 2E-12

-0.5-0.4-0.3-0.2-0.1

00.10.20.3

1969

-01-

0119

70-0

1-01

1971

-01-

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72-0

1-01

1973

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74-0

1-01

1975

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76-0

1-01

1977

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78-0

1-01

1979

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80-0

1-01

1981

-01-

0119

82-0

1-01

1983

-01-

0119

84-0

1-01

1985

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0119

86-0

1-01

1987

-01-

0119

88-0

1-01

1989

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0119

90-0

1-01

1991

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0119

92-0

1-01

1993

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94-0

1-01

1995

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96-0

1-01

1997

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98-0

1-01

1999

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0120

00-0

1-01

2001

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0120

02-0

1-01

2003

-01-

0120

04-0

1-01

2005

-01-

0120

06-0

1-01

2007

-01-

0120

08-0

1-01

2009

-01-

0120

10-0

1-01

2011

-01-

0120

12-0

1-01

2013

-01-

0120

14-0

1-01

2015

-01-

0120

16-0

1-01

2017

-01-

01

Residual of Quadratic Projection-Sewells Point

Boesch et al., 2018

Probabilistic 21st and 22nd century sea-level projectionsat a global network of tide-gauge sites (Kopp et al. 2014)BA13: Bamber and Aspinall [2013].GIC: glacier and ice cap.SMB: surface mass balance.

0.00

0.22

0.31

0.420.48

0.54

0.00

0.23

0.32

0.410.46

0.52

0.00

0.10

0.20

0.30

0.40

0.50

0.60

6/15

/199

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6/14

/200

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SLR

(m)

Quadratic-1995

K14

SLR future projection-Sewells Point

7

0

0.22

0.31

0.420.475

0.53

0

0.17

0.3

0.430.5

0

0.1

0.2

0.3

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0.5

0.6

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SLR

(m)

Current Old

SLR future projection-Sewells Point(Climate Resiliency Group)

SKY COVERAIR TEMPERATURE DEW POINT WIND

Equilibrium T (TE) Heat exchange coefficient (KT)

Hex program

∆T=KE(TE-T)/(Cp•V)

ICM Meteorological Forcing for Heat Transfer From Air to the Tidal Waters

Climate Change +∆Tair(2025) = 1.06 °C

Dew point recomputed

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f(T)=�𝑒𝑒−𝑘𝑘𝑘 𝑇𝑇−𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇 2 ,𝑇𝑇 ≤ 𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑒𝑒−𝑘𝑘2 𝑇𝑇−𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇 2,𝑇𝑇 > 𝑇𝑇𝑇𝑇𝑇𝑇𝑇𝑇

0

2

4

6

8

0 10 20 30 40

grow

th ra

te (d

-1)

Temperature (°C)

P3-Green Algae

revised old0

1

2

3

4

5

0 10 20 30 40

Gro

wth

rate

(d-1

)

Temperature (°C)

P1-Cyanobacteria

revised old

Revised temperature control on phytoplankton growth rate

From Carl Cerco

0

1

2

3

4

0 10 20 30

Gro

wth

rate

(d-1

)

Temperature (°C)

P2-Diatom

SATC recommendation

10

0

0.5

1

1.5

2

2.5

3

0 10 20 30

fact

or

Temprature (°C)

Old Revised

ar𝒆𝒆𝒆𝒆 = α𝒓𝒓𝑩𝑩𝒆𝒆𝒌𝒌𝒓𝒓(𝑻𝑻 − 𝑻𝑻𝑻𝑻)

Revised temperature control on phytoplankton repiration

SATC recommendation

Old: kr=0.0322Revised: kr = 0.069

2.4%

2.7%

2%

4%

2025Base 2025WIP

Nitr

ogen

load

incr

ease

(%)

3.1%

3.6%

0%

4%

2025Base 2025WIPPh

osph

orus

load

incr

ease

Nitrogen loading Phosphorus loading

Changes in nutrient loading in the 2025

From Gopal Bhatt11

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0.0

0.2

0.4

0.6

0.8

1.0

CB2.

1CB

2.2

CB3.

2CB

3.3C

CB4.

1CCB

4.2C

CB4.

3CCB

4.4

CB5.

1CB

5.2

CB5.

3CB

5.4

CB5.

5CB

6.2

CB7.

2CB

7.3

CB7.

4CB

8.1E

∆T

(℃)

Surface Bottom

2025 Air T increase 1.06

Summer surface water T change under 2025 CC (average 1993-1995)

Thomas et al 2017: data 1982-2014, 0.3 °C per decade;

Preston 2004: Data 1949-2002: 0.185 °C per decade; Bay head Bay mouth

T and ∆T profile at CB4.3Cunder 2025 CCC

S: surface; b: bottom; m: vertical average over 10 years.

Andrew Sommerlot

0 10 20 30Depth (m)

∆T

(° C/3

0yr)

0

2

4

-2

∆T

(° C/3

0yr)

0

2

4

-2

Summer

Annual

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Hypoxia volume (<1 mg/l) in summer (Jun-Sep) 1991-2000 in Whole Bay

2.96 2.773.05

3.26 3.12

0.94 0.95 1.05

0

1

2

3

4

Hypo

xia

volu

me

(km

3)-6% +3% +10% +5%

2025CC includes all climate change factors (SLR, Heat Flux and Nutrient loading)

Temperature effects

• Solubility: 0.9 °C increase decreases solubility by 0.13 mg/l, or 1.7%.

• Biological rates: increase 6% over 0.9 °C (Q10=2)

• Stratification (physics)

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2.96 33.08 3.12

3.26

2

2.5

3

3.5Hy

poxi

a vo

lum

e (k

m3)

Impact of T modified DO-solubility (DOS), biological rate and stratification (physics) on hypoxia volume in CB4MH (DO<1 mg/l summer 1990-2000)

50%37%13%Contribution

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Below Potomac Transect

CB4/CB5 Transect

CB3/CB4 Transect

CB2/CB3Transect

6,494 Base6640 SLR (2%)

7,236 Base7,374 SLR (2%)

4,7415,045 (6%)

5,3105,611 (6%)

1,9111,979 (4%)

2,3222,336 (1%)782

785

1,3561,352

Base = Beta 2 Calibration. SLR = 0.22m Sea Level Rise Scenario representing relative Chesapeake sea level riser from 1995 to 2050. Units in mean cubic meters per second (m3/s) for summer 1993 to 1995 hydrodynamics.

Toward OceanToward Head of Bay

Cross-transect water mass fluxesBase case versus sea level rise (SLR)Summer 1993-1995

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4.64.74.84.9

55.15.2

DO_DC (mg/l)

1.51.521.541.561.58

1.6

PP (g C/m2/day)

0.36

0.38

0.4

0.42

Resp_OW (mg/m3/day)

0.39

0.41

0.43

0.45

SOD (g C/m2/day)

10

11

12CL_OW (ug/L)

Diagnosis on Climate Change Scenarios, CB4,

average 1991-2000

19191919

Below Potomac Transect

CB4/CB5 Transect

CB2/CB3Transect

CB1/CB2Transect

9.2 Base9.2 SLR

2.4 Base2.4 SLR

10.710.9(2%)

3.33.5(6%)

9.29.2

1.81.87.6

7.6

0.60.6

Base = Beta 2 Calibration. SLR = 0.22m Sea Level Rise Scenario representing relative Chesapeake sea level rise from 1995 to 2025. Units in mean gram per second (g/s) averaged over June-Sep 1993-1995.

Toward OceanToward Head of Bay

Cross-transect TN fluxes: Base case versus sea level rise (SLR), summer 1993-1995

CB3/CB4 Transect

OBCTransect

8.08.0

0.90.9

10.810.8

3.63.6

Estimate on water quality attainment in the Deep Channel CB4MH Under the WIP condition

20

5.37

5.55

5.8

5.2

5.4

5.6

5.8

6.0

WIP2_LU2010 WIP2_LU2025 WIP2_2025CC

Exce

eden

ce(%

)

2025CC includes all climate change factors (SLR, Heat Flux and Nutrient loading)

+2 Mlbs N; -33 Klbs P

+4 Mlbs N; +370 Klbs P

Messages

• Temperature is the most sensitive variable in controlling DO under climate change conditions, followed by sea level rise and nutrient loading.

• Solubility contribute 50% to temperature effect.• Temperature deteriorates water quality whereas sea level rise

improves DO in the deep channel, with combined effect of 0.4% degradation of attainment under the WIP condition.

• Working on projection for 2035, 2045 and 2055.

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