OEAS 604: Final Exam

• Tuesday, 8 December• 8:30 – 11:30 pm• Room 3200, Research Innovation

Building I • Exam is cumulative• Questions similar to quizzes with

focus on concepts

Physical-biological Interactions OEAS 604

Lecture Outline

1) Recruitment to marine fisheries 2) Modeling physical-biological

interactions3) Global environmental change

programs

Recruitment patterns

Why patterns occur and what are key processes?

Changes in Abundance of Key Species

Calanus helgolandicusCalanus finmarchicus

mon

ths

Years (1958-1999)60657075808590951

23456789101112

0.20.40.60.811.21.41.6

6065707580859095123456789101112

0.10.20.30.40.50.60.70.80.91

Years (1958-1999)

Copepod abundance in North Sea

Consequences for fish production and recruitment

(Beaugrand)

Challenge • Recruitment to marine fish populations

depends on: • Variations in larval feeding and nutrition –

Lasker (1981)> larval feeding provides direct link from zooplankton to

the consumer

• Advection into favorable/unfavorable environmental conditions – Hjort (1914)

> requires knowledge of the scales that are relevant to the planktonic organism

Combining two requires understanding of dependence of population dynamics on the physical structure of the ocean and links to ecosystem dynamics

Scales of Processes

• View that marine ecosystems operate along a continuum defined by space and time

• Now - View has evolved to one in which marine ecosystem variability and population recruitment result from the integration of processes across all scales and includes direct as well as indirect interactions

Processes at all scalesinfluence variability of marine organisms and

populations

Studies of marineecosystems require

integration of theenvironmental drivers

and biological responses

Knowledge of scale interactions have resulted in additional hypotheses about physical-biological

controls on recruitment

Development of conceptual frameworks forrecruitment that encompass multiple scales

Trophic transfer andhabitat conditions

Field and Modeling Programs to Test Conceptual Models

Russia

Modeling Physical-Biological Interactions

• Modeling has been central to advancing understanding of physical-biological interactions

• Built on scientific and technological advances, such as realistic circulation models

• Integration of concentration-based models and IBMs with circulation models resulted in ability to project future states of ecosystems and to understand processes

• Allowed identification of spawning areas, recruitment regions, connectivity of populations at a range of scales

Understand the processes controlling thespring bloom

Used a regression model that included environmental variables – temperature

Riley (1946, JMR)

No predictivepower or indication ofcontrollingprocesses

Developed a mechanistic mathematical model

dP = P(Ph – R – G)dt

Time change P = photosynthesis – respiration – grazing

Included processes that affect the concentration and abundance of phytoplankton

Physical-biological modelsevolved to systems of

interconnected modules

NEMURO - minimum trophic structure and biological

relationships … thought to be essential in describing

ecosystem dynamics in the North Pacific

Realistic RegionalCirculation Models

Coastal Gulfof Alaska

West Antarctic Peninsula

Include sea ice, couplingto atmospheric modelsand larger scale models

Connection between spawning and recruitment regions

Inclusion of detailed biology provides process understanding

Population connectivity at regional to circumpolar scales

Importanceof

comparativestudies

Thorpe et al. (2007)

FutureModels evolving

to include humansas part of the

marine food web

Importance of top predatorsincluding humans

Perry et al. (in press)

Barange et al. (in press)

Tuna Forage Model

New Production

Temperature, Currents, Plankton Biomass, Oxygen

Populationvariability

Age Structured Model

Fishing catch

CLIOTOP

Global Environmental Change Programs

• Integrated Marine Biogeochemistry and Ecosystem Research (IMBER) Program

• Surface Ocean-Lower Atmosphere (SOLAS)• Land-Ocean Interactions in the Coastal Zone

(LOICZ)• Past Global Changes (PAGES)• International research programs sponsored by

the International Geosphere-Biosphere Programme (IGBP) and the Scientific Committee on Oceanic Research (SCOR)

IMBERIMBERFOUR RESEARCHFOUR RESEARCH

THEMESTHEMES

Interactions between biogeochemical cycles and marine food webs

Sensitivity to global change

Feedbacks to the Earth System

Responses of society

SOLAS• understand the key biogeochemical-physical

interactions and feedbacks between the ocean and atmosphere

• Exchange processes at the air-sea interface and the role of transport and transformation in the atmospheric and oceanic boundary layers

• Air-sea flux of CO2 and other long-lived radiatively active gases

LOICZ

• support sustainability and adaptation to global change in the coastal zone

• include developing and testing integrated multidisciplinary (natural+economic+social) methods to analyze the environmental and social interactions and feedbacks governing coastal system status and changes

PAGES

• improve our understanding of past changes in the Earth System in order to improve projections of future climate and environment, and inform strategies for sustainability

Future Earth

COP21

Next Class

• Instruments and models• Chapter 6, Talley et al.