© Yann Arthus-Bertrand / Altitude

Changing Ocean, Marine Ecosystems,

and Dependent Communities

Nathan Bindoff

7 October 2017, Lautoka, Fiji

Multiple lines of robust

evidence support the

conclusion that many

aspects of the climate

system have changed.

Warming in the climate system is unequivocal

The oceans have warmed.

0-700 m

temperature

trend, 1971-2010

Zonal average

Human influence on the

climate system is clear

Changes in key physical and biogeochemical properties and processes, including the deep ocean and

relevant ocean regions, modes of variability, teleconnections and their feedbacks on the climate system

A global view of oxygen loss over the past 50 years, largely fueled by warming, yields 2%loss, but much greater regional losses.

Multiple mechanisms drive oxygen loss in the open ocean and generate climate feedbacks

OCEAN DEOXYGENATION

Schmidtko et al. 2017; Levin, 2018

Changes to resource ratios are usually ignored

Changes to resource ratios shape ecosystems (long history in ecology)

Key example: Fe/N ratio shaping success (or not) of nitrogen fixing algae

Ward et al. (2013; Limnol. Oceanogr.)

Resource ratios are changing in the north Pacific (and perhaps elsewhere …)

Kim et al. (2014; Science)

We need to think about relative changes and the impacts on the productivity and ecosystems

1 2

Catches and livelihood

Loss of USD 10 billion in revenue per year, 35% more than loss of catches.

Lam et al. (2016). Sci. Rep.

Projected impacts on fish stocks and

fisheries

Human communities (wellbeing)

Nutrition

Countries that are highly dependent on seafood-sourced micro-nutrient (e.g., omega-3-fatty acid, zinc) are projected to have largest decrease in catches under climate change.

Golden et al. (2016) Nature.

Reefs at risk in the western pacific. Reefs at risk revisited. Burke et al 2011

Worst affected SIDS by the consequences of

climate change by share GDP: Pacific Region.

(UN-OHRLLS)

Chapter 5: Outline

Executive Summary

1. Introduction

2. Changing Oceans and Biodiversity

3. Changing Marine Ecosystem Services and Human

Wellbeing

4. Solutions and Governance

5. Synthesis

© Yann Arthus-Bertrand / Altitude

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