The geological past contains many examples of Earth's climate being different to today and these are excellent test beds for our understanding of the climate system and ultimately our predictions of our future climate. Over the last 600 thousand years (kyr) or so, the Earth's climate has regularly oscillated, roughly every 100 kyr, between warm "interglacial" periods with climates similar to today, and frigid "glacial" periods when several kilometres of ice blanketed North America and northern Europe (at times extending into Siberia). Bubbles of ancient air trapped in ice cores from Antarctica reveal that these cyclical changes in climate were partly driven by changes in the atmospheric concentration of the greenhouse gas carbon dioxide (CO2) - CO2 was low during glacial periods and high during intervening interglacial periods. During each ice age cycle, cooling towards peak glacial climates tended to be rather slow (taking around 90 kyr) whereas the warming that terminates each glacial period tended to be very quick (~10 kyr in length). However, before about 1.2 million years ago Earth's climate was warmer on average, there was less ice on the continents and climate cycles were more regular, symmetric, and shorter - they followed a 41 kyr orbital beat at that time. Gradually between 1.2 and 0.6 million years ago, the character of glacial-interglacial cycles changed, shifting from these smaller 41-kyr cycles to the more recent larger 100-kyr cycles. Climate scientists have studied this important interval, known as the Mid Pleistocene Transition (MPT), for decades to learn about the inner workings of the climate system, but as yet the underlying cause remains debated. Despite their contrasting character, these two types of climate cycle were both paced by subtle variations in the amount and the spatial and seasonal distribution of sunlight reaching the Earth's surface as a result of regular changes in how the Earth orbits the sun (known as orbital cycles). What is puzzling is that the change in the nature of the climate cycles occurred in the absence of any notable change in these orbital cycles. It therefore represents a fundamental change in the way the climate system operates and in particular how certain feedbacks behave when the climate system is subjected to forcing. In order to test which, if any, of the available models adequately explains this transition we need reconstructions of both the size of the continental ice sheets and knowledge of the concentration of atmospheric CO2. While the evolution of ice volume through time is known relatively well, the direct ice core record of atmospheric CO2 only covers the last 800 thousand years and it is unlikely that it can be extended further back in the near future (if at all). We therefore have to use other, more indirect methods to reconstruct the CO2 content of the ancient atmosphere. One approach with a proven track record uses the boron (B) isotopic composition of calcareous microfossils called foraminifera, which steadily accumulate over time in deep-sea sediments. There are two naturally occurring isotopes of boron and the ratio of these two isotopes, 11B to 10B, in the shells of foraminifera reflects the acidity of the ocean surface when they lived, and from this it is possible to estimate atmospheric CO2 at that time. The principal aim of this proposal is to use this method to produce a record of CO2 for the last 1.3 million years that overlaps with the ice core CO2 record but then extends this back to cover the Mid Pleistocene Transition. Putting our current understanding of the MPT to the test in this way promises new insights into the coupling of climate change and the global carbon cycle, thereby also ultimately shedding light on how climate and polar ice sheets will respond to fossil fuel burning.

International climate talks in Katowice, Poland, in 2018 descended into acrimony over a scientific landmark report by the most authoritative international body on climate science, the Intergovernmental Panel on Climate Change (IPCC). Saudi Arabia, Kuwait, Russia, and the United States--four big oil and gas producers--refused to endorse an IPCC special report. This report stated that limiting global warming to 1.5C reduces climate-related risks, but requires deep emission reductions in all sectors. Since these reductions are costly, governments may have political incentives to try to influence how these reports are written and used. We study how and under what conditions governments seek to influence the production of science in the IPCC; and the effects of this attempted influence on climate negotiations and domestic climate policymaking. Our research comes at a vital moment for international climate politics. In order to meet the 1.5C-2C temperature target agreed in the Paris Agreement in 2015, countries need to increase their climate action. As the pressure to decarbonise the global economy mounts, the IPCC's forthcoming Sixth Assessment Report in 2022 will provide states with the latest knowledge on the scientific basis; impacts, adaptation, and vulnerability; and mitigation of climate change. The key findings from this comprehensive assessment will serve as scientific input to United Nations climate negotiations and guide governments' climate policies for the decade to come. Despite its key role, the IPCC's 6-8 year assessment cycles have come under repeated criticism for different reasons. Our systematic study of countries' engagement with IPCC processes will hence contribute to the practical and scholarly discussion on how the IPCC can best fulfil its mandate of being policy-relevant in the new climate landscape the Paris Agreement has created. In this unique context, we will offer new theoretical and empirical insights into the strategies, conditions, and effects of attempted government influence in international climate science policy. The theoretical framework, which we will develop, will allow us to analyse governments' strategic involvement in the production of IPCC reports and their uptake in climate policymaking. While "interference" and "obstruction" at both stages is documented in the literature, our framework will help us to hypothesise how, when, and with what effects governments seek influence in the global climate science-policy interface. Our systematic empirical analysis will benefit from a mixed methods approach. We will combine qualitative and quantitative methods, including elite interviews; participant observation; comparative case studies; document analysis; regression models; and text-as-data approaches. This multifaceted approach will enrich our empirical understanding of government influence in the IPCC and will help us to overcome the methodological challenge that government influence is not always readily observable. Together with our advisory board, which includes senior IPCC leadership and assessment authors, and through partnerships with leading climate research institutes--CICERO (Center for International Climate Research) in Norway; PIK (Potsdam Institute for Climate Impact Research) in Germany; Cardiff University's Centre for Climate Change and Social Transformations (CAST); and the Tyndall Centre for Climate Change Research in the UK--we intend to create impact from translating our research findings into feasible and implementable proposals to inform ongoing discussions about IPCC reform. We will furthermore present our findings at the United Nations climate conference in winter 2023 and, over the course of the project, disseminate our research to a wider audience through blog posts, podcasts, and on social media.

MERLiN is series of modelling studies designed to assess the limits of Greenhouse Gas Removal (GGR) effectiveness for prevention of climate change impacts, climate change reversibility, and the accounting of GGR. Global temperature rise is determined by cumulative emissions of CO2, with climate policy temperature targets corresponding to emissions budgets e.g. 2K = around 1000 Gt C emitted. GGR is suggested as a way of recapturing CO2 some time after it has been emitted such that the eventual net quantity emitted meets a temperature target budget. Current climate mitigation action appears reliant on future application of GGR in this role to meet the international climate warming targets of the UNFCCC Paris Agreement of less than 2K and ideally 1.5K warming. However, even if the same eventual budget is attained, it is expected that climate change impacts resulting from an emissions overshoot and later recapture pathway will be different to impacts associated with pathways in which no recapture is required. This difference in impacts sets limits to the contribution of GGR to avoiding dangerous climate change impacts. MERLiN is designed to determine these limits, and develop simple metrics relating the difference in committed climate change impacts to the amount and duration of emissions budget excess. MERLiN will also, with international collaborators, investigate climate change reversibility, and how the Earth system (in particular the carbon cycle) respond to GGR recapture of CO2. Here, different timescales in carbon cycle components create inertia whereby emission and later recapture of CO2 do not have equal (cancelling) temperature effect. This creates an accounting challenge for GGR which MERLiN will investigate and quantify. These results are crucial to informing policy choices and actions on GGR. Using MERLiN researcher's strong policy experience, MERLiN will translate and communicate its findings on climate change impact GGR limits, climate change reversibility, and GGR accounting to inform policy-makers on the implications for climate mitigation action, policies and mechanisms.

The work to help internationalise ADVENT and facilitate assessment of its findings in the long term will be conducted in three phases. In the initial phase, KAPtEN and ADVENT teams will produce a set of questions and initial statements that are relevant internationally and that will be explored further, building on ADVENT's four initial workshops. In particular, a workshop on the role of energy in ecosystem services and natural capital conceptual frameworks will set the basis for characterising the impacts of specific energy chains and energy infrastructure development on the UK's marine, aquatic, coastal and terrestrial environments, and understand how different means of sourcing energy from outside the UK would impact global ecosystem services. Similarly, a workshop on currently projected energy pathways will look at what we currently know about the nexus between energy, land and water and the trade-offs and synergies associated with different patterns of energy development. These are important topics that will grow with the increasing pressure and desire to move towards a sustainable use of resources. The very first contribution of KAPtEN will be to develop a simplified web portal to facilitate the crowd-sourcing of a literature review around each of the questions and statements arising from these workshops, which will be turned into a databank of resources exportable in reference management systems (e.g. Endnote). In the second phase, a new, professional-looking and easy to use ICT platform will be developed and tested on the valuation of Energy and Nature together. The principle behind the ICT platform is that users more easily react to statements that are already made, by confirming or contradicting them. Thus the ICT platform will start from a set of key statements that together will form the 'Map of Current Knowledge' - or the MoCK. The ICT platform hosting the MoCK statements will include options to link new research papers and to explain how these papers support, challenge, or contradict the existing statements. Anyone can link papers, not just the authors. This is the crowd-sourcing part of the project. If a paper is linked to a MoCK statement, the authors (who are the 'experts'), will be invited to revise the explanations if they wish and to rank other papers up or down, so that with time the papers voted 'up' by most experts will appear at the top. In the final phase, we will publish 10-20 key statements on the valuation of Energy and Nature together, in a joint ADVENT-KAPtEN effort, including international partners, and co-chaired by senior colleagues with extensive experience, to be submitted to a high-impact journal (e.g. Nature Energy). These 10-20 statements will be the ADVENT MoCK that will be posted on the KAPtEN ICT platform and start the continuous assessment process of forming the Map of New Knowledge - or the MoNK. We will use our extensive networks through connections with our international partners, Future Earth, Tyndall Centre partners, IPBES, IPCC and others to invite people to link their papers and show how they inform the assessment made in ADVENT with their international knowledge. As the KAPtEN ICT platform develops, we will be working with Future Earth and IPBES partners to develop other MoCKs, so that with time, KAPtEN will make a step change in our capacity to transparently and continuously assess the state of science, inter-link fields such as Energy and Nature, and inform policy of the environment and beyond. One of our international project partner said 'this ICT platform has the potential to revolutionize the way scientific assessments are done, by opening up the process for contributions by the entire research community, and by establishing a transparent yet organized set of rules to highlight the emerging consensus and issues'.

This project aims to improve the program development process, using a process of "Type-driven Development". We believe that in order to enable the highest levels of productivity, programming should be a conversation between the programmer and the machine. In type-driven development, we begin by giving a type as a plan for a program. Then the machine, rather than being seen as an adversary which rejects incomplete or incorrect programs, is the programmer's assistant. A limited form of this idea exists in modern integrated development environments: when typing "x." into a text buffer, the environment will show with methods "x" implements. This project will take this idea several steps further. Not only can we give feedback on partial programs, we can also use types and their structure to generate significant parts of a program and direct the implementation of more complex components such as communication and security protocols. During development, programs spend most of their time in an incomplete state, and the act of programming is as much about the steps required to achieve a complete program as it is about the end result. Accordingly, language implementations and tools must support the editing process as well as check and compile the end result. In this project, we will develop the necessary tooling to support interactive type-driven development, based on sound theoretical foundations. Furthermore, we will make the tooling itself programmable: the foundations will essentially give a language of programming "tactics", which will be composable intro sophisticated methods for automatic program construction, directed by the type. We will liaise with industry throughout to ensure that the techniques we develop are well-suited to commercially relevant problems.