WP 4: Climate Change and Ocean Acidification 2nd Annual Meeting Paris, 14-16 May 2012 MACROES

WP 4: Climate Change

and Ocean Acidification

2nd Annual MeetingParis, 14-16 May 2012MACROES

WP4: Climate Change and Ocean Acidification

WP4 main objectives:

--- Use the MACROES modelling framework to study the effects of anthropogenic emissions (greenhouse gases, aerosols) through climate change and ocean acidification on the marine ecosystems (incl. fish ressources)

--- A particular emphasis will be given to the identification and characterization of the feedbacks between the different (natural) systems considered here (climate, biogeochemical cycles, marine ecosystems)

WP4 structure:

--- 4.1 Impact of CC and OA on marine ecosystems: end-to-end--- 4.2 Retroactions in the coupled system

- Top-down control from higher to lower trophic levels- Biophysical coupling through heat trapping and bio-induced turbulence

--- 4.3 Impact of CC and OA on marine ecosystems: biodiversity

WP4: Climate Change and Ocean Acidification

Les « drivers » : productivité marine, acidification, dé-oxygénation

Les premières simulations avec IPSL-CM / PISCES-APECOSM

A venir cette année…

Climate Change impact on surface chlorophyll

250

450

650

850

6.0

3.0

0.0

RCP8.5RCP6.0RCP4.5RCP2.6Historical

T (°C)

Chl de surface (mgChl/m3)

0.15

0.17

0.19

Premiers Résultats avec CM5

CO2, T et chlorophylle de surface

Biogeochemical Drivers

• Changes in Net Primary Productivity driven by climate change



Net Primary Productivity as simulated by 8 CMIP5 models

IPSL-CM5A-LR IPSL-CM5A-MR MIROC-ESM-CHEM

MIROC-ESM HadGEM2-ESHadGEM2-CC

MPI-ESM

CanESM2

IPSL-CM5

IPSL-CM5 Biogéochimie Marine : Séférian et al. in pressComparaison des modèles IPCC – CMIP5 / Productivité marine :Kidston et al. in prep

IPSL-CM5A-LRIPSL-CM5A-MRMPIM-ESMMIROC-ESMMIROC-ESM-CHEMCanESM2HadGEM2-ESHadGEM2-CC



A global decrease of NPP by -5 to -18% in 2100

Relative Change in NPP from 2005 to 2100 (RCP85 scenario)



Relative Change in NPP from 2005 to 2100 (RCP85 scenario, model-mean, %)

Hatched regions: when >75% of the models agree on the sign of change

Large regional contrasts: -50% in N. Atl, -20% in the tropics, increase in the SO


• Changes in pH / Ocean Acidification



RCP4.5

RCP8.5

Orr et al. in prep

IPSL-CM5A-LR, IPSL-CM5A-MR, HadGEM2-ES, HadGEM2-CC, MPIM-ESM, MIROC-ESM, MIROC-ESM-CHEM, CanESM

Consistent decrease in pH from several CMIP5 models

RCP45: -0.3RCP85: from -0.4 to -0.8 in 2300 !



RCP4.5

RCP8.5

Aragonite / Calcite undersaturation reached at the surface in polar oceans

Implications on calcification / trophic food webs?

[CO32-]



RCP4.5

RCP8.5

Increase in C/N ratios of organic matter (Riebesell et al. 2008)

Implications on food “quality” ?

(Tagliabue et al. 2011)


• Changes in Oxygen / Desoxygenation



Stramma et al. 2008

Observed increase of hypoxic waters in the Eq. Pacific

O

2 (

mo

l/L)Changes in [O2] (micromol/L) (5-model mean, SRES-A2) : 0 m



Large decrease of O2 in surface waters: solubility-driven


(IPSL-CM4, UVIC, CSM1.4, CCSM3, BCM-C)

O

2 (

mo

l/L)Changes in [O2] (micromol/L) (5-model mean, SRES-A2) : 200 m



Consistent at mid/high lat but models do not agree in the tropics !


Towards coupled climate & end-to-end ecosystem modelling

Towards Online Coupling: PISCES-APECOSM


PISCES-APECOSM :: Preliminary RCP85 results (see talk by S. Dueri for more details)

Nanophytoplankton relative change Diatoms relative change

Microzooplankton relative change Mesozooplankton relative change

15% drop of total biomass in 2100 compared to preindustrial values

Large disparity among plankton functional types:Phyto : -8%, Diatoms : -16%, Microzoo : -20%, Mesozoo : -20%.

Latit

ude

Time(1850 to 2100)

LOWER TROPHIC


PISCES-APECOSM :: Preliminary RCP85 results

Latit

ude

Time(1850 to 2100)

Total biomass relative change Epipelagic biomass relative change

Migratory biomass relative change Mesopelagic relative change

23% drop of total biomass in 2100 compared to preindustrial values

Large disparity among communities:Epipelagic : -22%, Migratory : -8%, Mesopelagic : -30%

UPPER TROPHIC

Etapes / Stratégie pour le WP4 End-to-End

Etape 1M12 : Simulations “offline” sur 1860-2100 (RCP8.5)

IPSL-CM ( PISCES APECOSM ) M18 : Analyse de l’impact du CC (et OA) sur les écosystèmes

Etape 2

M24: Mise en place de PISCES-APECOSM dans IPSL-CM (biomixing) M24 : Importance du top-down control dans un contexte de CC

IPSL-CM ( PISCES APECOSM )

Etape 3M42: Simulations “offline” sur 2000-2100 (biodiversité)

IPSL-CM PISCES-APECOSM-DEB/Biodiv (?)M48: Analyse de ces simulations

En

co

urs

Climatic scenarios:Climatic scenarios:

Governance scenarios:Governance scenarios:

IPSL model

3.Fishing scenarios ?

E2E model

2. Retroactions

1. Sensitivity (acidification ?)


Some issues: spatial resolution, internal variability, model spread

Model Spread? : use of CMIP5 models ?

Spatial resolution? : towards higher resolution (global) / regional configurations ?

Internal variability?

Climate simulations: difficult to use for the next decade or so (2010-2030) asinternal variability tends to dominate on these time-scales

?

Some issues: spatial resolution, internal variability, model spread

Model Spread?

Spatial resolution?

Internal variability?

10 members

Ensemble mean

Decadaly-smoothed control run

50 ansSéférian et al. in prep

-Some decadal predictions with climate models in IPCC-AR5

(over 2000-2030, with initialization procedure)

-Do models have some previsibility skills for marine productivity evolution?

PP in North Atlantic simulated by IPSL-PISCES

Documents

WP 4: Climate Change and Ocean Acidification 2nd Annual Meeting Paris, 14-16 May 2012 MACROES