To better constrain the long-term response of Earth's climate system to continuing greenhouse gas emissions, it is essential to turn to the past. A key advance would be to understand the shift in Earth's climate response to orbital forcing during the 'Mid-Pleistocene transition' [MPT, 900,000 (900 kyr) to 1.2 million years (1.2 Myr) ago], when a dominant 40 kyr cyclicity gave way to the current 100 kyr period. It is critical to understand the role of forcing factors and especially of greenhouse gases in this transition. Unravelling such key linkages between the carbon cycle, ice sheets, atmosphere and ocean behaviour is vital, assisting society to design an effective mitigation and adaptation strategy for climate change. Only ice cores contain direct and quantitative information about past climate forcing and atmospheric responses. However, the longest (EPICA) ice core record available to date covers only the last 800 kyr. The RIA Topic LC-CLA-08-2018 empowers the European ice core community to perform such an oldest ice core drilling and the project 'Beyond EPICA' is taking on this unique challenge and opportunity. The overarching scientific objective driving 'Beyond EPICA' is to obtain quantitative, high-resolution ice- core information on climate and environmental changes over the last 1.5 Myr. The cause and effect relationship that led to the enigmatic MPT change in the climate system is not understood yet, as important information on global changes in the climate system is still missing. Most of this information, including the phasing of these changes in the Earth System can only be derived from a continuous ice core from Antarctica covering the last 1.5 Myr. This proposal uses the planning derived during the recent BE-OI CSA, and offers an excellent team (the only team globally that could at present accept the challenge of the call), underpinned by excellent infrastructure and capacity, and is currently ensuring it has an excellent location for the core.

To better constrain the response of Earth’s climate system to continuing emissions, it is essential to turn to the past. A key advance would be to understand the transition in Earth’s climate response to changes in orbital forcing during the 'mid-Pleistocene transition' (900 to 1200 thousand years ago) and in particular the role of greenhouse gases. Unravelling such key linkages between the carbon cycle, ice sheets, atmosphere and ocean behaviour is vital for society to better design effective mitigation and adaptation strategies. Only ice cores contain the unique and quantitative information about past climate forcing and atmospheric responses. But the ice providing essential evidence about past mechanisms of climate change more than 1 Ma ago required for our understanding of these changes (termed the “Oldest Ice” core), has not been found to date. The consortium BEYOND EPICA – OLDEST ICE (BE-OI), formed by 14 European institutions, takes on this challenge to prepare the ground for obtaining 1.5 million year old ice from East Antarctica. BE-OI has the objectives to: - support the site selection through creation and synthesis of all necessary information on Antarctic sites through specific geophysical surveys and the use of fast drilling tools to qualify sites and validate the age of their ice; - select and evaluate the optimum drill site for the future “Oldest Ice” core project and establish a science and management plan for a future drilling; - coordinate the technical and scientific planning to ensure the availability of the technical means to implement suitable drill systems and analytical methodologies for a future ice-core drilling, and of well-trained personnel to operate them successfully; - establish the budget and the financial background for a future deep-drilling campaign; - embed the scientific aims of an “Oldest Ice” core project within the wider paleoclimate data and modelling communities through international and cross-disciplinary cooperation.