The TiPES project have a stunning number of 50 deliveries over the course of the project. Below some of the scientific deliveries are available.
D1.1 Open access proxy data repository Paleoclimate records are essential for identifying Tipping points in the Earth’s past and to properly understand the climate system’s underlying bifurcation mechanisms. Due to their varying quality, resolution, and dating methods, identifying the most relevant paleo-records is, therewith, a daunting task. To address this problem, we created the PaleoJump database, which compiles high-resolution paleoclimate records originating in ice, marine sediments, speleothems, loess, and lake sediments. To allow easy access and navigation, the database has the form of a website, a working version of which is currently online. It includes a map of the paleoclimate records, as well as tables which list supplementary information for each record. As the database is continuously developed and has not yet been peerreviewed, the link to the website is currently only available on request.
In D1.3 : Spatial patterns of the interrelations between different Tipping Elements we have analyzed a large set of paleoclimate proxy archives, available publicly in the TiPES database on
past abrupt transitions (https://paleojump.github.io). We considered different time scales, ranging from
Pleistocene Glacial Cycles to the current Holocene. Upon a careful review of available proxy records,
strongly building upon the TiPES proxy database published alongside deliverable D1.1, we focussed on
the Dansgaard-Oeschger (DO) events during the last glacial interval, i.e. rapid Northern-Hemisphere
warming transitions of regionally up to 15° within a few decades, which we consider the archetype of
abrupt climate transitions evidenced in paleoclimate proxy records. In addition to their relevance, the
data coverage is exceptionally high for these events, making them ideal for investigating to what extent
reliable statements about spatial patterns of the causal interrelations between transition events in
different subsystems of the Earth can be made.
D2.1 Modelling protocol for DO events Dansgaard-Oeschger (DO) events are abrupt, large climate swings that punctuated the last glacial period. There is uncertainty whether current IPCC-relevant models can effectively represent the processes that cause DO events. Current Earth system models (ESMs) seem overly stable against external perturbations and incapable of reproducing most abrupt climate changes of the past (Valdes, 2011). If this holds true, this could noticeably influence their capability to predict future abrupt transitions, with significant consequences for their use in the identification of Tipping Elements (TEs), and more in general, for the delivery of precise climate change projections. In this task, the objectives of this study are twofold: (1) to compile and analyse model output for any spontaneously oscillating simulations, and (2) to formulate possible pathways to a DO PMIP (Paleoclimate Modelling Intercomparison Project) protocol that could help investigate cold-period instabilities through a range of insolation-, freshwater-, GHG-, and NH ice sheet-related forcings, as well as evaluating the possibility of spontaneous internal oscillations. Such a model protocol is crucial since (1), there is currently no PMIP common guidance to investigate DO events, (2) it could help carry out simulations in ESM and Earth system models of intermediate complexity (EMIC) under a common framework, and (3) it will be essential in guiding a more methodical search for DO events in current models
D3.1 Analysis and modelling of tipping elements in future climates
In this work we aim to improve understanding of whether a collapse of the AMOC could happen in
future as a result of global warming, and to develop tools that could help society to become resilient to
this risk. We especially focus on the possibility of developing an early warning system that would allow
time to adapt or to accelerate efforts to slow down climate change, if it were discovered that an AMOC
collapse was imminent. We have also worked to improve understanding of the impact of an AMOC
collapse, if it occurred, on another area of the climate system that is vulnerable to tipping points,
namely the Amazon rainforest
D3.4 Indian summer monsoon projections under regional and
global forcings. The aim of this report is to establish the state of the Indian monsoon within future climate scenarios, and to define safe operating spaces to exclude dangerous conditions
over the Indian region. This is accomplished through climate modelling studies and
comparison of the results to previous studies.
D4.1 State dependence and spatial patterns of feedbacks is a progress report on work undertaken as part of TiPES on some of the key indicators of climate
change – namely climate response, feedbacks and sensitivity. These are metrics that quantify how much
the climate is expected to change depending on how forcing such as atmospheric CO2 changes in the
future. More specifically, TiPES has been examining how these metrics may depend not just on forcing,
but also on the state of the climate itself. Indeed, the current climate state may not be so obvious to
observe: potentially, there may be more than one stable state and, one of the big challenges is to
separate the internal variability from forced variability. In case of more than one stable climate states,
transitions between different equilibria may appear as abrupt climate changes. Moreover, feedbacks
may change their relative strength over time on a variety of timescales, such that the climate response
changes underway during the transient towards a new equilibrium.
This work done in TiPES has has been looking at (a) better understanding of climate variability on a
variety of time scales (b) improved methods of quantifying sensitivity and climate response with and
without tipping points (c) improved methods of quantifying spatial and temporal patterns of climate
feedbacks from transient simulations (d) exploring some of these methods against earth system models
of varying complexity.
This publication provides teaching material for an introductory course on functional and dependently
typed programming and its application to verified decision-making in the context of climate science,
using the computational theory of policy advice and avoidability developed by Botta et al.(, ).
D6.2 Domain-specific-language with basic notions about Tipping Points This deliverable reports on an ontology of climate science notions for tipping point research and on a domain-specific language (DSL) for policy advice under deep threshold uncertainty. The ontology and the domain-specific language have been designed to assist the specification and the verified solution of stylised climate decision problems. Applications of the ontology and of the DSL are discussed in related publications.
D7.2 Summary of Report: State of the art on Tipping Points This report represents Deliverable 7.2 which, owing to the Covid situation, could not be based on an expert public meeting but has instead been produced on the basis of past and present science results of the partners of TiPES, as well as the available scientific literature.