Dear Editors:
Please find attached our manuscript “Anthropogenic ocean biogeochemistry change over the twenty-first century
and implications for marine biota and people” that we would like to be considered for publication in Nature.
In this study, we provide, to our knowledge, the most comprehensive and up-to-date report of projected climatedriven changes in the ocean biogeochemistry, its potential stress upon marine biota and likely ramifications upon
human welfare due to the impending demise of marine goods and services.
We consider the interdisciplinary nature, topicality and timeliness of this manuscript make publication in a journal
as influential as Nature very important. This work has brought together climate modelers of the Coupled Model
Intercomparison Project Phase 5 (CMIP5) and researchers in biological and social sciences; provides important
input into the debate over climate ‘loss and damage’ stemming from the Doha Conference of the Parties; and will be
one of the few multi-disciplinary papers utilizing the state-of-the-art CMIP5 dataset published in time for citation by
Working Group II of the IPCC’s 5th Assessment report.
At every step of this project, we ensured a comprehensive and global overview by including all available data; this
report is unique at integrating Earth System models, marine biodiversity and social economic data and in quantifying
some of the broader biological and social implications of ocean biogeochemical change.
First, the paper makes use of all climate data projections contributed as part of the CMIP5. As of July 2012, the
CMIP5 included projections from 32 different Earth System Models on temperature, pH, oxygen and primary food
production for the global ocean in three dimensions. This inclusive consideration of all model outputs posed a
considerable technical challenge (see supplements 2 and 3) but allowed to assess patterns of inter-model variability
and add to the robustness of general projections (see table S2). In total, we analyzed over 27000 years of modeled
data for all parameters considered here (see supplement 3). Animations of biogeochemical changes from all models
are available to you and reviewers in the following page, which is currently password protected; but that will be
made publicly available after publication:
http://www.soc.hawaii.edu/mora/CMIP5/DataByModel.html
User name: mora_cmip5
password: aloha
Second, the paper collected all available data on the global distribution of marine habitats and biodiversity hotspots
to assess their level of exposure to projected changes in temperature, oxygen, pH, and primary food production. We
are not aware of such an analysis being undertaken previously, especially while considering multiple
biogeochemical parameters associated with ongoing CO2 emissions. These results suggest that changes in multiple
parameters will occur simultaneously upon all marine biota, highlighting the potential for biological synergies and
the considerable challenge for species as several physiological adaptations will be needed to cope with ocean
biogeochemical change.
Finally, the paper takes a bold step toward integrating climate research and social economic data to quantify the
fraction of the world human population likely to be vulnerable to projected climate change in the ocean. According
to this calculation between 470 and 870 million people live in low-income countries whose exclusive economic
zones will face considerable climate change and are highly dependent on the ocean for jobs, revenues and food.
These results suggest that human dependence on marine goods and services is substantial, particularly among lowincome countries. This socio-economic disparity highlights a considerable challenge for social adaption to climate
change, and an unfair divide between those who benefit economically from the processes creating climate change
and those who will have to pay most of the environmental and social cost.
We believe that these results will have implications beyond the fields brought together to facilitate our
comprehensive analysis, and hope that this work will act as a focal point for the climate impacts community over the
coming years as comprehensive analysis of the CMIP5 results takes off, and the social and political demand for
climate impact information rapidly evolves. Additionally, we consider that the large amounts of data mastered here
will have diverse uses further contributing to the paper’s appeal.
The paper has been edited according to a Letter to Nature. The manuscript is 2000 words long and includes only 3
figures (comprising 17 panels), and a Supplement with extended results and methods.
Thank you for consideration and we look forward to hearing from you.
Camilo Mora, Ph.D.
Corresponding author, Department of Geography, University of Hawaii, 2424 Maile Way Honolulu, Hawaii 96822
USA. Phone: (808) 956 7093. E-mail: cmora@hawaii.edu
100-word summary of the paper's appeal to a popular (non-scientific) audience
Available Earth System Models predict remarkably similar trends over the next century in ocean warming,
acidification, oxygen depletion and primary food shortfalls under expected CO2 scenarios. Marine ecosystems will
be simultaneously exposed to such biogeochemical changes making them prone to synergistic responses and
reduced biological resilience as numerous physiological adaptations will be required. The impact of ocean change
on human welfare could also be considerable as ~470 to ~870 million of the poorest people in the world have heavy
reliance on the ocean for food, jobs and revenues and live in countries that will experience the largest ocean
biochemistry changes.