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Our Common Future Under Climate Change

Climate Change Challenges Ecological Function in the Deep Half of the Planet

Lisa A. Levin

Center for Marine Biodiversity and Conservation Scripps Institution of Oceanography, UC San Diego, USA

July 8, 2015

UPMC, Paris, France

CMBC

50 years ago … This generation has altered the composition of the atmosphere on a global scale through radioactive materials and a steady increase in carbon dioxide from the burning of fossil fuels. - President Lyndon B. Johnson, 1965

50 year later…. This generation has begun to alter the deep ocean…. Via CO2-induced environmental change and resource exploitation

Delving Deeper

• The deep sea – what is at stake?

• Climate Change (T, OA, O2) in deep water

• Consequences for biodiversity & ecosystem function – Past, Present and Future

• A growing human footprint – Clash of climate and exploitation

The largest habitat on earth

• The deep ocean (>200 m) comprises 2/3 of the planet’s surface area and > 90% of its habitable volume

• We have seen < 5% of the deep sea floor thus most marine species are undescribed. • Great depth limits access & measurement capability

•Cold (2-4o C) •Dark (no sunlight) •High Pressure (1 atm/10 m)

•Homogeneous •Stable •Food Limited

THE FIRST 100 YEARS

What Do We Know about the Deep Sea? Why should we care?

New exploration tools reveal a wealth of environmental heterogeneity

SENTRY (AUV)

ABE (AUV)

Photo:D. Stevens

Jason (ROV)

DTIS (photo by D. Stevens)

MULTI BEAM SONAR

HOV

AUV

ACOUSTICS

Seamounts- Underwater Volcanoes 30,000-50,000!

Dense fish aggregations

Crusts rich in cobalt, titanium, nickel, platinum, cerium molybdenum, tellurium,

Lush invertebrate populations

Exceptional Longevity, Slow Growth

Garrardia sp. Leiopathes sp.

2,320 years old

Smooth oreo dory – 100 y Black Oreo-153 y

Sablefish – 114 y

Orange Roughy - 149 y

Sablefish – 114 y

DEEP CANYONS

Photo by P. Tyler

VULNERABLE BIOTIC REEFS

Photo - MAREANO

DEEP CORAL REEFS

Natural Resources Canada

SPONGE REEFS

Pribillof Canyon – M. Ridgeway

Manganese Nodule Fields

• Cover vast areas of the ocean • Nodules grow slowly < 1 cm/million years • Valuable minerals resources (Mn, Ni, Cu, Co)

Cu, Gold, Zn, Silver

Metals News

clccharter.org

en.wikipedia.org

Worlds without sunlight Hydrothermal Vents

Oil, Gas, Gas Hydrates

Methane Seeps Oxygen Minimum Zones

Phosphorites

Courtesy of Rashid Sumalia

The Deep Pelagic Largest migrations, Food for commercial fishes Unknown biodiversity, Genetic resources

Ecosystem Services from the Deep

Provisioning: – Fish & shellfish

– Energy

– Pharmaceuticals

– Industrial agents

– Minerals

Monk fish

Photograph by Peter Batson

Support Functions

**Habitat** -Substrate -Nursery -Refugia -Trophic Support

Methane seeps as shark and ray nurseries

(Treude et al. 2011)

Fish larvae in sea pens

Baillon et al. 2012 http://blog.sylviaearlealliance.org/ 2011_06_01_archive.html

CHILE Mediterranean

Sponges as rockfish nurseries

Species – novel symbioses, behaviors, tolerances

Genes – GENETIC POTENTIAL TO ADAPT TO CHANGE!

Enzymes - e.g. cold water detergents, UV resistance

Metabolites/Drugs – antibiotics, anticancer, anti-inflammatory

Biomaterials – sponge fiber optics - coral bone grafts Anti fouling – for marine or medical

Detoxification – Methyl mercury

Cellulases – fermentation

Pyrolase – used in fracking

Biodiversity as a service

Photograph by Peter Batson

Gulf of Mexico Courtesty of E. Cordes, C. Fisher

Regulating Services: Deep-sea ecosystems are linked to the surface

ocean, the atmosphere and land

The ocean has taken up 28% of CO2 emissions and 93% of heat (since 70s). Photosynthetic production by phytoplankton sinks or is carried to the deep sea (biological pump) 6 month lag Surface pollutants find their way to the deep sea

Heat Uptake Carbon Sequestration Nutrient cycling

$125B/y

Scientific Research Communications Movies, Books, Art Avatar

Artwork by Lily Simonson Artwork by Tanya Young

Rising CO2 emissions

Deoxygenation Lower O2 solubility & Ventilation

OMZ Expansion

Acidification

Warming Ocean

Warming

Atmosphere

Reduced POC Flux

Ice cap melting

Enhanced Stratification

UPWELLING

CO2 + CO32- + H2O ↔ 2HCO3

-

Reduced vertical mixing

Warmer water holds less O2

Projected Change on the Deep-Sea Floor - 2100 (Mora et al. 2013)

T O2

pH POC

What are the biodiversity consequences?

Figure courtesy Ariel Anbar and Timothy Lyons.

Geologic record holds a long history of environmental change and biodiversity consequences

Episodic Anoxia (red) and Extinction Events

BEST PAST ANALOG TO CURRENT CLIMATE CHANGE

ADVENT OF OXYGENATION

PETM CAMBRIAN EXPLOSION

% E

XTI

NC

TIO

N

Sperling et al., 2013, PNAS 110: 13446

Pre-Cambrian Oxygenation and advent of carnivory may help explain the timing and diversity increase

of the Cambrian Explosion (540 MY)

drill holes

nemerteans

chaetognath

The PETM at 55 MY exhibits the deadly trifecta: Rising CO2, and T, declining O2

From Norris et al. 2013

WARMING, ANOXIA, ACIDIFICATION L. Alegret , S. Ortiz , E. Molina , 2009, Palaeo 3

(Alamedilla section -Southern Spain)

55.8 MY: Rapid extinction and recovery of benthic foraminifera across the Paleocene–Eocene Thermal Maximum

No/g % Agglut. %Inf. a H’

Recent Deep-Ocean Warming based on repeat hydrography

Rate of warming below 4000 m

Purkey and Johnson (2010)

Study Finds Earth’s Ocean Abyss Has Not Warmed

> 2000

Llovel et al. Nature Climate Change 2015

Deep Argo

Nature Climate Change 2015

Warming to > 1.4oC has allowed a

Lithodid crab invasion in the Palmer Deep,

Antarctica

< 850 m No crabs

> 950 m With crabs

BIODIVERSITY CONSEQUENCES

Smith et al. Proc. R. Soc. B 2011

Neolithodes yaldwyni

Warming may dissociate gas hydrates, pervasive throughout the margins and expand seep ecosystems

www.soundwaves.usgs.gov

pH Changes North Pacific Total pH Change (1991-2006) Atmospheric CO2 + respiration

North Atlantic Deepwater formation draws down high- CO2 water with transport by boundary currents.

17-21% of N. Atlantic seafloor > 500 m will experience a 0.2 unit drop in pH by 2100.

Byrne et al. 2010

Gehlen et al. 2015

Norwegian corals

Norwegian Corals

Differences in aragonite saturation between ocean basins affect deep-water calcifiers.

Paicifc OMZ corals

Ωarag = [Ca2+][CO3

2-]/Ksp

Temperature rise and saturation state decline will induce loss of habitat suitability for Australian deep-sea corals

Omegaarag > 0.9 and T 7° C

Solenosmilia variabilis projection for 2100

Thresher et al. 2015 Nature Climate Change

Hypoxia is widespread in the oceans at upper bathyal depths

200 m

800 m

Oxygen minimum zones (OMZs)

Blood Pigments (Hemoglobin) Enhanced Surface Area

OMZ’s are not Dead Zones! Adaptations Abound

Small body size long/thin shape

Functional Consequences of Low O2 in OMZs

Altered Carbon Processing

Altered Size Structure and Composition

Rapid Diversity Shifts

Woulds et al. 2007, Levin et al. 2009, Gooday et al. 2009, Levin et al. 2013

Pakistan margin

Foraminifera Macrofauna Megafauna Nekton

Reduced Bioturbation

Reduced Colonization

700m 737m 800m 850m

900m 940m 1050m 1100m

14 of 28

stations (50%)

have zero

predators

ANOVA: F3, 64 = 20.4

p < 0.0001

Sperling et al., 2013, PNAS 110: 13446

Very low oxygen is associated with loss of carnivores in OMZ sediments (Polychaeta)

ANOVA: F3, 64 = 14.25

p < 0.0001

OMZ

(200-300 m)

Above/Below OMZ

(100, 500, 800 m)

Chemosynthesis is common among metazoans within the OMZ

Light C and N signatures reflect influence of chemosynthesis.

North Chile Margin (Iquique)

Thyasirids

Lucinoma aequizonata

Acharax

Olavius crassitunicatus

Siboglinids

TAXA WITH CHEMOAUTOTROPHIC SYMBIONTS

Oxygen decline in the tropical O2 minima

Stramma et al. 2010

O2 in 1964-70 vs 1990-2008 from 200-700 m in tropics, subtropics At 200 m the area with < 70 mM O2 has increased by 4.5 million km2 area

Ocean Deoxygenation

OXYGEN DECLINES in the NORTHEAST PACIFIC OCEAN

Station P

Whitney et al. 2007

26.9 isopycnal

Oxygen loss of 0.67mM O2/y

Stn P

Crawford and Pena 2013

Oregon 50 m

Bograd et al. 2014

So. Cal. Bight

Last 50 y

British Columbia

Pierce et al. 2012

OMZ

By

Day

Habitat Compression W

AT

ER

DE

PT

H

Vertical migrators – underpinning the food chain & nutrient cycling experience

Koslow et al. 2011 After Siebel 2011

Pacific groundfish distributions move shallower, northward for species unable to tolerate O2 < 60 mM

depth of 60 mM O2

Whitney and Sinclair (Unpublished)

Hypoxia-induced loss of bottom-fish habitat in the NE Pacific

By 2050 - 50% loss of their depth range

Present

2050

2003

Slope

Upper Slope

Outer Shelf

Sea Urchins make up ~80% biomass

Urchins, crustaceans, fish

Fish and Inverts

2013

Bograd et al. (2008)

Upslope migration of sea urchins: Habitat compression for some Habitat expansion for others

Southern California margin

Lytechinus pictus

Strongylocentrotus fragilis

Sato, Levin, Tran, Schiff, Luong and So. CA Coastal Water Research Project

S. fragilis Test porosity

S. fragilis Growth rate

200 250 300 350 400 450 540

200 250 300 350 400 450 540

How can we untangle interacting effects of climate change?

Areas of convergent climate change from 1999-2099 Bopp et al. 2013

Bopp et al. 2013 Temperature Primary Productivity

Oxygen

How can we untangle interacting climate variables?

Areas of convergent climate change projected from 1999-2099

pH

Oxygen Minimum Zones are Carbon Maximum Zones

A model system for the study of multiple climate variables stressors

Paulmier et al. 2011

Recent avg Temp at 800 m

Volcano 7 Mexico

Chile

OMZ BENTHIC TRANSECTS - 95 stations – published literature and unpublished VARIANCE PARTITIONING – Regression Trees and Random Forests

Sperling, Frieder & Levin, in review

Macrobenthos:

• Diversity

• Evenness

Use of natural gradients on OMZ/CMZ margins to unravel

effects of multiple climate stressors (O2, pCO2, and T) on diversity

100-3400 m

Polychaetes

Echinoderms

Crustaceans

Molluscs

The OMZ Biota

Sperling, Frieder, Levin, in review

Oxygen is the overriding factor controlling macrobenthos diversity (H’log2) in the Pacific

Threshold at 0.16 ml/l (7mM)

Threshold at 900 matm

0.5 ml/l (22mM)

Sperling, Frieder, Levin, in review

Temperature is the overriding factor controlling macrobenthos evenness

Temperature thresholds occur at 8-10oC

R2 = 0.25

Identification of newly vulnerable regions in the E. Pacific where deoxygenation and warming coincide

Columbia California Peru Panama Baja Costa Rica

Depth m

0 500 1000

1500

Sperling, Frieder, Levin, in review

Industrialization of the Deep Ocean

Demanding more: RAW MATERIALS

A growing population

ENERGY FOOD

RISING CO2

Warming Acidification Deoxygenation

RARE EARTHS

Technology - The enabler

Satellite guided GPS New cables and gear to reach deep

New mining tools

Offshoreenergytoday.com deepseanews.com

Nature.com en.wikipedia.org

Mapping Tools

Oil and Gas Infrastructure

SOURCES OF HETEROGENEITY

• Large-Scale:

– Hydrographic

(O2, pH, T, S)

– Productivity

• Meso-Scale:

– Geomorphic

– Geochemical

• Small-Scale:

– Biogenic Structures

Seamounts

Canyons & Fjords

Oxygen minima

Mn nodule Fields Canyons

Cold water coral & sponge reefs

Hydrothermal Vents Methane Seeps

Climate Change + Human Disturbance

= LOSS OF RESILIENCE?

T O2

pH POC

Sites of greatest warming are also subject to most intense bottom trawling

Trawling

Temperature stress may reduce reslience and recovery from disturbance

Ocean Acidification may exacerbate trawl or mining damage to deep-water corals with cascading biodiversity consequences

Puig et al. 2012

http://blogs.nature.com/news/2010/

DpH

Cold-water corals

Deep trawling

Ocean Acidification may weaken corals and slow recovery from trawl damage with cascading biodiversity consequences

Puig et al. 2012

http://blogs.nature.com/news/2010/

DpH

Cold-water corals

Deep trawling

• Expanding OMZs :

Ocean deoxygenation may reduce recovery following mining disturbance on the upper slope

Stramma et al. 2010 Oxygen loss from 1960s to 2000s

How can we untangle interacting effects of climate change?

Areas of convergent climate change from 1999-2099 Bopp et al. 2013

Bopp et al. 2013

The greatest threats to biodiversity will come from the intersection of climate change with direct human activities

Mn Nodules

Cobalt Crusts

Massive Sulfides

Phosphorites

Climate-induced stressors: Temperature, pH, Oxygen, Primary Production Direct human activities: Fishing, Oil & Gas, Minerals Extraction

What future for the deep half of the planet?

• Deep-sea diversity and function are sensitive to CO2 emissions, which cause warming, acidification and deoxygenation.

• The deep ocean plays an essential role in removing CO2 and heat from the atmosphere. We rely on the deep ocean for a healthy planet!

• Recognize climate change as a cumulative impact - with interactions among stressors and with direct human activities in the deep ocean.

• Develop a global ‘deep’ observing network targeting ecosystems and regions at the nexus of climate change and deep-sea industrialization.

• Incorporate climate change into holistic environmental planning in the deep ocean.

http://www.indeep-project.org/deep-ocean-stewardship-initiative

Deep-Ocean Stewardship Initiative Ta

nya

Yo

un

g

DOSI seeks to integrate science, technology, policy, law and economics to advise on ecosystem-based management of resource use in the deep ocean and strategies to maintain the integrity of deep-ocean ecosystems

within and beyond national jurisdictions

MERCI

Thank you for listening !

Danke

Abhivandanam

Merci

Gracias

Dankie

Ke a leboha

Ngiyabonga Jai-rruh-jef

Spasibo

Nee-kay

Ayo

Na pandura

Okuhepa

Iyaloo

Obrigada

Shukran

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