INTRIGUED: INvestigating The Role of the North Pacific In Glacial and Deglacial CO2 and Climate

Lead Research Organisation: University of St Andrews
Department Name: Earth and Environmental Sciences

Abstract

The geological record offers an invaluable window into the different ways earth's climate can operate. The most recent large-scale changes in earth's climate, prior to modern climate change, were the Pleistocene glacial cycles, which feature growth and disintegration of large ice sheets, rapid shifts in major rain belts, and abrupt changes in ocean circulation. Changes in atmospheric CO2 concentrations, reconstructed from air bubbles in ice cores, are intimately linked with these ice age climate events. Indeed the close coupling of CO2 and temperature over glacial-interglacial cycles has become an iconic image in climate science, a poster child for the importance of CO2 in climate, and the natural template against which to compare current man-made CO2 rise.
However despite the high profile of glacial-interglacial CO2 change, we still don't fully understand its cause. The leading hypotheses for glacial CO2 change involve increased CO2 uptake by the ocean during ice ages, which is vented to the atmosphere during deglaciation. However despite decades of work these hypotheses have had few direct tests, due to a lack of data on CO2 storage in the glacial ocean. One of the most glaring holes in our understanding of ice age CO2 and climate change is the behaviour of the Pacific. This basin contains half of global ocean volume, and ~30 times more CO2 than the atmosphere, and so its behaviour will have global impact. It has also recently been suggested that the North Pacific may play an active role in deglacial CO2 rise, with local deep water formation helping to release CO2 from the deep ocean to the atmosphere. If correct, this hypothesis provides a new view of Earth's climate system, with deep water able to form in each high latitude basin in the recent past, and the North Pacific potentially playing a pivotal role in deglaciation. However few data exist to test either the long-standing ideas on the Pacific's role in glacial CO2 storage, nor the more recent hypothesis that North Pacific deep water contributed to rapid deglacial CO2 rise. Given the size of the Pacific CO2 reservoir, our lack of knowledge on its behaviour is a major barrier to a full understanding of glacial-interglacial CO2 change and the climate of the ice ages.
This proposal aims to transform our understanding of ice age CO2 and climate change, by investigating how the deep North Pacific stored CO2 during ice ages, and released it back to the atmosphere during deglaciations. We will use cutting-edge geochemical measurements of boron isotopes in microfossil shells (which record the behaviour of CO2 in seawater) and radiocarbon (which records how recently deep waters left the surface ocean), on recently collected samples from deep ocean sediment cores. By comparing these new records to other published data, we will be able to distinguish between different mechanisms of CO2 storage in the deep Pacific, and to test the extent of North Pacific deep water formation and CO2 release during the last deglaciation. We will also improve the techniques used to make boron isotope measurements, and add new constraints on the relationship between boron isotopes and seawater CO2 chemistry, which will help other groups using this technique to study CO2 change. To help us understand more about the mechanisms of changes in CO2 and ocean circulation, and provide synergy with scientists in other related disciplines, we will compare our data to results from earth system models, and collaborate with experts on nutrient cycling and climate dynamics. Our project will ultimately improve understanding of CO2 exchange between the ocean and the atmosphere, which is an important factor for predicting the path of future climate change.

Planned Impact

1. Workshop on ice age climate change delivered to schools through Geobus (Secondary school students and teachers):

Secondary school students, teachers, and their families will benefit from educational outreach that we will undertake as part of the University of St Andrews' Geobus initiative. Geobus provides teaching and resources in the earth and environmental sciences to secondary schools across Scotland and the North of England. We will develop a Geobus workshop on ice age oceans and climate change, showing how high-school level physics and chemistry may be applied to understand ocean-atmosphere CO2 exchange, global albedo, and deep ocean circulation. The topical nature of climate change makes it an excellent topic with which to engage students in STEM subjects, a key goal for UK education and economic development.

2. Edinburgh Science Festival (General public-children and families; adults):


Building on the workshop developed with the expertise of the Geobus team, we will apply to bring a workshop on ice age climate change to the Edinburgh Science Festival. This will feature hands-on experiments that teach the fundamental science underpinning climate change past and present. We will pitch a project that uses CO2 and pH loggers, water tanks, and floating candles to measure the effect of burning fossil fuels on CO2 in the atmosphere and the ocean. PI Rae will also give an evening lecture to adults on the science of deglaciation, featuring drink mixing of different colours and densities to simulate ocean circulation, and ice input to simulate different sea level rise scenarios.

3. Improved scientific understanding of the climate system (Climate scientists, policy makers, and their constituents):

This project will provide new insights into ocean-atmosphere CO2 exchange, links between changes in rainfall and abrupt changes in ocean circulation and climate, and deglaciation of major ice sheets. These components of the climate system have the potential to change rapidly in the next few hundred years, so improved knowledge of how they can operate, and of any potential 'tipping points' in the climate system, is required by policy makers for the benefit of the general public. To ensure effective dissemination of our research results throughout the climate science field, PI Rae will organise a session at the AGU fall meeting in year two of this project, in collaboration with our project partners. To establish a direct link with policy makers, PI Rae will meet with the Member of Parliament for NE Fife, to discuss the science underlying anthropogenic climate change.

4. Climate change teaching moments (General Public and Policy Makers):

The proposed research covers a broad range of topical climate topics, providing excellent teaching moments to engage with the general public. We will use the St Andrews press office to help disseminate our key findings, and their relationship to modern climate change, to the media. PI Rae's recent paper on this topic was effectively publicised in this way, making the front page of the Herald, and garnering coverage in the Times of India, the Daily Mirror, and Daily Mail. PI Rae will also maintain an active blog on this research on his group website, and promote the project's progression on Facebook and Twitter. PI Rae is an active tweeter and will continue to use this platform as a means to reach a broad audience.

5. Training of young researchers (Young researchers and UK STEM community):

The project will train two undergraduate students in laboratory techniques, research methods, and scientific writing, with impact assessed through a project report, and inclusion on manuscripts. The project will also train a PDRA in radiocarbon and boron isotope analyses. The multi-disciplinary nature of this project, with involvement of a strong and diverse network of project partners, will further enhance the PDRA's training and career deve
 
Description We have found pulses of CO2-rich waters reaching the surface ocean in the North Pacific during specific intervals of rapid climate change during the last deglaciation. We have used new model data comparisons to work out the mechanism for changes in CO2 release and pulses of biological productivity and hypoxia. We have also found that similar pulses of productivity occur during each of the rapid climate change events of the last 100 kyr. Finally we have shown that during the last glacial maximum there was an enhanced Pacific Meridional Overturning Circulation (PMOC), which contributed to changes in productivity and temperature in this region - and may even have aided early human migration to North America.

We have found a Southward expansion of the North Pacific gyre boundary at the last glacial maximum

We have possible signals of propagating North Pacific deep water in the W Equatorial Pacific
Exploitation Route We are following this initial result up with increased data resolution. In future these data will be a valuable modelling target and may notably improve understanding of rapid CO2 change. The discovery of enhanced glacial PMOC has already been taken on as a target for state of the art climate models. The discovery of enhanced glacial PMOC is also of intense interest to the archeological community, for its impact on the habitability of Beringia, prior to the first peopling of North America.
Sectors Education,Energy,Environment,Culture, Heritage, Museums and Collections

 
Description They have contributed to outreach activities carried out through Geobus
First Year Of Impact 2015
Sector Education
Impact Types Cultural,Societal,Policy & public services

 
Description CDISK4 Research Cruise 
Organisation California Institute of Technology
Department Division of Geological and Planetary Sciences
Country United States 
Sector Academic/University 
PI Contribution Our group provided expertise in foraminiferal ecology, geochemistry, and proxy calibration. This was crucial for the overall project goal of determining the carbonate budget and carbon cycling of the North Pacific.
Collaborator Contribution The Caltech and USC groups secured NSF funding for the CDISK4 cruise and invited us to participate. They also made crucial carbonate chemistry and hydrographic measurements that allow us to improve proxy calibration in this region, a key component of this project. We have also gained new insights into the carbon cycle of this region in the modern, which will inform our paleo reconstructions.
Impact Recent presentations at AGU Ocean Sciences 2018. A feature length film on the expedition is also in production.
Start Year 2017
 
Description CDISK4 Research Cruise 
Organisation University of Southern California
Department College of Letters, Arts and Sciences
Country United States 
Sector Academic/University 
PI Contribution Our group provided expertise in foraminiferal ecology, geochemistry, and proxy calibration. This was crucial for the overall project goal of determining the carbonate budget and carbon cycling of the North Pacific.
Collaborator Contribution The Caltech and USC groups secured NSF funding for the CDISK4 cruise and invited us to participate. They also made crucial carbonate chemistry and hydrographic measurements that allow us to improve proxy calibration in this region, a key component of this project. We have also gained new insights into the carbon cycle of this region in the modern, which will inform our paleo reconstructions.
Impact Recent presentations at AGU Ocean Sciences 2018. A feature length film on the expedition is also in production.
Start Year 2017
 
Description North Pacific climate dynamics 
Organisation ETH Zurich
Country Switzerland 
Sector Academic/University 
PI Contribution Contribution of data and expertise on the past behaviour of the North Pacific ocean
Collaborator Contribution Model output and expertise on climate dynamics
Impact 2 draft manuscripts
Start Year 2013
 
Description Southern Ocean dynamics 
Organisation University of California, Los Angeles (UCLA)
Department UCLA Atmospheric and Oceanic Sciences
PI Contribution We have contributed new data and ideas based on our paleoceanographic reconstructions that have motivated a new set of modelling approaches, forming the basis of a new PhD studentship project at St Andrews in Collaboration with our colleagues in the School of Mathematics.
Collaborator Contribution Our partners have contributed significant expertise in mathematical modelling and instigated a joint PhD studentship, which they have day to day responsibility for.
Impact Not yet - it has just commenced.
Start Year 2017
 
Description Southern Ocean dynamics 
Organisation University of St Andrews
Department School of Mathematics and Statistics
Country United Kingdom 
Sector Academic/University 
PI Contribution We have contributed new data and ideas based on our paleoceanographic reconstructions that have motivated a new set of modelling approaches, forming the basis of a new PhD studentship project at St Andrews in Collaboration with our colleagues in the School of Mathematics.
Collaborator Contribution Our partners have contributed significant expertise in mathematical modelling and instigated a joint PhD studentship, which they have day to day responsibility for.
Impact Not yet - it has just commenced.
Start Year 2017
 
Description CPD event for Scottish Geography Teachers 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Schools
Results and Impact At the Scottish Association of Geography Teachers annual conference we ran two 50 minute sessions with 15 teachers in each session. Each workshop was made up of a series of kitchen cupboard still experiments to help explain climate. Teachers will provided with the power point, worksheets and experiment instructions to be able to disseminate information to their classes.
Year(s) Of Engagement Activity 2016
 
Description Delivery of climate workshop to secondary school pupils 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Schools
Results and Impact In 2016 GeoBus delivered a series of workshops to National 5 and Higher level students looking at the causes and impacts of climate change from July to December we worked with 486 students. The pupils feedback on the workshop, this feedback has been used to improve the workshop that is being delivered in 2017. So fair 105 pupils have taken part in the workshop and a further 300 are booked to participate between now and the end of May.

The workshops have been designed to provide practical activities linking to climate science, to allow students to speak to experts and to insure that they are making decisions based on up-to-date facts.
Year(s) Of Engagement Activity 2016,2017
URL https://geobus.st-andrews.ac.uk/whatweoffer/workshops/
 
Description Development of online resources promoting good practice when teaching climate science. These resources are linked to the 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Schools
Results and Impact The online resources are being developed by the GeoBus team over an 18 month period July 2016 -December 2017. These resources include a series of lesson plans under 4 titles:
* It's happening: Evidence of Climate Change
* It's Us: Causes of Climate Change
* It's Serious: Impact of Climate Change
* It's Solvable:Solutions to Climate Change

These resources can be downloaded and taught by teachers all over the world but are specifically linked to the Scottish and English curriculum, from March 2017 we will be able to track the downloads of resource. The assumption is that it will be educators who download the resources and will disseminate the lessons to there classes. the average class size is 20 pupils for science class and 30 for a social science class. The resources have sparked interest from teachers and international educators (AGU) who have asked for similar resources to be produced in the future.
Year(s) Of Engagement Activity 2016,2017
URL https://geobus.st-andrews.ac.uk/resources/carbon-capture-storage/
 
Description Production of 4 Geology in a minute videos 
Form Of Engagement Activity A broadcast e.g. TV/radio/film/podcast (other than news/press)
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact GeoBus has a YouTube channel. In June and July 2016 four minute long videos were produced.
* What is the Green House Effect?
*What is Ice-albedo feedback?
* What are the impacts of climate change?
*What's different this time?

These videos are short and designed to answer a specific question related to climate change, they have been watch in countries all over the world and viewing is steadily increasing. A short video means that more people are likely to stop and watch it, by having the titles as questions people are more likely to come across the video when searching online.
Year(s) Of Engagement Activity 2016
URL https://www.youtube.com/channel/UC0Sry1dA-hGuThgTKu4iGNg
 
Description Twitter take over: speak to the Expert 
Form Of Engagement Activity Engagement focused website, blog or social media channel
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Media (as a channel to the public)
Results and Impact GeoBus linked up with the Scottish Governments for Climate week and provide Dr James Rae with a opportunity to take over the GeoBus twitter account. Through out the week schools and the public could ask James questions link to his research. The take over made of 43,000 impressions on twitter, the success has meant we will run a similar take over next year.

As a result of the take over questions were asked that allowed us to further develop our online resources.
Year(s) Of Engagement Activity 2016