Processes responsible for formation and development of the early Earth (> 2500Ma) are not
well understood and strongly debated, reflecting in part the poorly preserved, altered, and
incomplete nature of the geological record from this time.
In this session we encourage the presentation of new approaches and models for the development of Earth's early crust and mantle and their methods of interaction. We encourage contributions from the study of the preserved rock archive as well as geodynamic models of crustal and mantle dynamics so as to better understand the genesis and evolution of continental crust and the stabilization of cratons.
We invite abstracts from a large range of disciplines including geodynamics, geology, geochemistry, and petrology but also studies of early atmosphere, biosphere and early life relevant to this period of Earth history.

The geological record provides insight into how climate processes may operate and evolve in a high CO2 environment and the nature of the climate system during a turnover from icehouse to greenhouse state — a transition that may potentially occur in the near future. Palaeoenvironmental records and climate models are two contrasting and yet complementary sources of information on past climates. Both approaches independently generate insights into the dynamics of the climate system. However, more information can be extracted about the drivers of climate variability and change when the two approaches are combined. The aim of this session is to share progress in our understanding of global changes based on the integration of geochemical/paleobotanical/sedimentological techniques and numerical models. We invite abstracts that reconstruct Earth’s climate, investigate how the interconnections of the key surface reservoirs (vegetation-ocean-atmosphere-cryosphere-biogeochemistry) impact climate, identify tipping points and thresholds and studies that use climate model outputs to understand the physical controls of climate variability. Pertinent themes may include greenhouse-icehouse transitions and intervals testifying for extreme changes.
We are pleased to have Martin Ziegler as our invited speaker talking about "Cenozoic climate evolution revealed by clumped isotope thermometry".

This session aims to showcase an interesting diversity of state-of-art advances in all aspects of Phanerozoic stratigraphy, paleoceanography, paleoclimatology, eustasy, and orogeny on long- and short timescales in marine and terrestrial environments. Within this broad topic, contributions include but are not limited to, case studies of organic and inorganic geochemistry, sedimentology, paleontology, and modeling, alongside integrated approaches to understanding evolving earth processes, particularly climate transitions and their consequences. The session will potentially be organized into thematic blocks to allow more in-depth exploration and discussion of topics.

Orbital forcing is the most important known external driver of the climate system. Nevertheless, resultant internal climate feedbacks that invoke different climate components across different time scales play a critical role in defining the climate response to orbital forcing. These internal climate feedbacks are particularly apparent at past climate transitions, which cannot be simply explained by orbital changes alone (e.g. glacial inception and termination, the mid-Brunhes transition, the mid-Pleistocene transition, Pliocene-Pleistocene transition).

In this interdisciplinary session, we aim to bring together studies of centennial-to-orbital scale interactions among the atmosphere-ocean system, cryosphere, and carbon cycle that advance our understanding of the climate system during climate transitions. Modeling, theoretical and proxy-based studies as well as novel methodologies that combine the above approaches are especially encouraged.

Keynote talk "Ocean carbon storage and release over a glacial cycle" by Dr. James Rae, School of Earth & Environmental Sciences, University of St Andrews

Public information:
In this session, online displays will be present mainly by live talks in “GoToMeeting” room (similar as Zoom). Since some of authors cannot join in online video chat room, the conveners will try to make essential information accessible in the text-based chat room. In addition, we will eventually move to the chat room after the talks in “GoToMeeting” room. Here is the room information:
----------------------------------------------------
EGU2020 online session CL1.8
Fri, May 8, 2020 1:55 PM - 3:45 PM (CEST)

Please join my meeting from your computer, tablet or smartphone.
https://global.gotomeeting.com/join/880800221

You can also dial in using your phone.
Germany: +49 892 0194 301

Access Code: 880-800-221

Reconstructions of past climate conditions have clearly demonstrated that the spatio-temporal variability of Earth´s climate is paced by orbital forcing and tectonic processes. However, the mechanisms that translate these forcing signals into climate changes and subsequently geoarchives continue to be debated. We invite submissions that explore the climate system response to various forcing mechanisms, and that test the stability of these relationships under different climate regimes or across evolving climate states during the Phanerozoic. A special focus is given to the Pliocene epoch between ~5.3 to 2.7 Ma, which has been proposed as an analogue for future climates, since it is characterised by CO2 concentrations which align with those recorded today and projected for the end of this century under moderate emissions scenarios.
Submissions exploring proxy data and/or modelling work are welcomed, as this session aims to bring together proxy-based, theoretical and/or modelling studies focused on global and regional climate and ecosystem responses to orbital, tectonic and ocean gateway forcing at different time scales. We also encourage contributions linked to the PAGES-PlioVAR and PlioMIP2 programmes.

Abrupt climate change is a recurring feature of the Earth’s history and the current anthropogenic interference has set the climate system on a potential abrupt change trajectory. As with past climate change, future climate changes are not predicted to affect all areas of the planet in the same way, or at the same rate, yet mechanisms for spatiotemporal differences are complex and difficult to predict from low-resolution global models.
Increasingly detailed high temporal resolution proxy reconstructions of past abrupt climate transitions and oscillations (such as the Late Glacial-Holocene transition, Heinrich Stadials or the Dansgaard-Oeschger cycles) have been produced for widely distributed ice core, marine and terrestrial records. When precisely integrated (i.e. via cosmogenic isotopes, palaeomagnetic excursions, tephra) these now allow for an integrated assessment of the anatomy, the spatially variable consequences and the mechanisms of abrupt climate transitions.
With a focus on the period from the last interglacial to the pre-Industrial, this session will assess methodologies (numerical and/or proxy based) and findings from studies of the spatiotemporal anatomy of the climate system on decadal to millennial timescales. We invite contributions that evidence regional climate thresholds and gradients, explore their consequences for human societies and identify mechanisms from the integration of local to global proxy records as well as modelling approaches. Finally, we explore how findings from such precisely integrated records in space and time can serve to quantify vulnerabilities and regional thresholds relevant for the anthropogenic climate change trajectory.

Public information:
The session will run May 6 from 10:45 to 12:30 in the text-based chat of the EGU website:
https://meetingorganizer.copernicus.org/EGU2020/displays/36721

with an additional moderation and presentation in a Zoom meeting room, see details in the Session materials. Please join the text based chat and if you can also the Zoom room. We have decided to add Zoom to make the session more personal and to give authors the chance to introduce their work in person. If you can’t/don’t want to/are not allowed to use Zoom, don’t worry, we as the conveners will try to make all information accessible in the text based chat. Please see the session materials for schedule and detailed instructions.

The carbon cycle and climate are tightly linked over millennia and centennial time scale, as is exemplified by the synchronous changes between CO2 and Antarctic temperature recorded in ice cores. Aside from CO2, other data such as carbon isotopes also show strong changes in the carbon cycle between the colder Last Glacial Maximum and warmer pre-industrial. However, despite decades of research with data and climate models, no complete explanation has emerged to account for all data records. We invite contributions from both proxy data and models tackling these issues and bringing new insights on the carbon cycle changes during the Last Glacial Maximum and last deglaciation. In particular, we welcome contributions from models of all complexities from simple theoretical models to complex GCMs, as well as new records or interpretation of proxy data from ice and sediment cores, spanning centennial to millennial time scales and involving ocean or land processes.
Our invited speaker will be Alice Marzocchi talking about "Global cooling linked to increased glacial carbon storage via changes in Antarctic sea ice".

Ice cores are a key archive to study past climate variability. Various physico-chemical proxies provide key insights into past temperature, atmospheric composition, volcanic activity, and atmospheric circulation. Despite the large body of empirical information available, we still lack a detailed, process-based understanding of the creation of the archived climatic signal. This session aims, in light of the new "Beyond EPICA Oldest Ice" (BE-OI) ice-core project, at an in-depth discussion on the extent to which climatic signals are archived in the proxy signals, how the archival processes – from the atmosphere to the surface to post-depositional changes in the firn and ice and even further smoothing/diffusion in the lower most part of the ice column – themselves affect the recorded signal, and how to optimally recover the original signals from existing ice-core records. We welcome contributions that shed light on this chain of processes, including interpretation of various proxies from new, or existing, ice core records from Antarctica, Greenland or high mountainous areas; analyses of climate model, reanalysis and back trajectory data; novel application of statistical and spectral methods to proxy data; or new measurement techniques. Finally, we encourage discussion about the impact the individual processes have on the relationship between proxy and past climate variability across various temporal and spatial scales.

Public information:
Brief live chat info (10:45 am - 12:30 pm CET Tuesday 5th May)
- 10:45 am - 11:45 am: discussion of the uploaded presentations (similar to PICO sessions)
where presenters can explain their slides/answer questions
- 11:45 am - 12:30 pm: group discussion on 2 to 3 broader topics based on the themes of
the presentations
- We encourage short powerpoint presentations (1-3 slides)
- Choose a single focus and main conclusion from your presented research

Earth history is punctuated by major extinction events, by perturbations of global biogeochemical cycles and by rapid climate shifts. Investigation of these events in Earth history is based on accurate and integrated stratigraphy. This session will bring together specialists in litho-, bio-, chemo-, magneto-, cyclo-, sequence-, and chronostratigraphy with paleontologists, paleoclimatologists and paleoceanographers. An emphasis is placed upon the use of a variety of tools for deciphering sedimentary records and their stratigraphy across intervals of major environmental change. This session is organized by the International Subcommission on Stratigraphic Classification (ISSC) of the International Commission on Stratigraphy (ICS) and it is open to the Earth science community at large.

Public information:
During the chat, on Tue 05 May, 16:15–18:00, all 10 abstracts with uploaded display material will be open for discussion. The conveners will moderate the chat discussion. We will discuss the abstracts in the order in which they appear in the program. After we call an abstract, we ask the author to provide the chat room with a 1-2 line summary of their work (best to copy-paste a pre-written sentence). Then we can proceed to Q&A. We kindly ask all chat room participants to keep the chat on subject, and not to disrupt the Q&A.

Of course, if you upload your display last-minute, we will also make time to discuss yours. Don't hesitate to share your science!

Significant advances in our understanding of the Meso- and Cenozoic development of polar regions have been made over the last two decades by studying continental shelf, slope, or deep sea sediment sequences. These include more detailed reconstructions of the climatic, oceanographic, and tectonic evolution of high northern and southern latitudes over various time scales, as well as reconstructions of past ice-sheet dynamics and studies of marine geohazards. Data have been obtained from conventional and high-resolution 2D and 3D seismic surveying, as well as from a growing number of short sediment cores and targeted high-latitude deep drilling expeditions (e.g. IODP, MeBO). The same techniques have also been applied in fjords, which link the continental margins with the interiors of landmasses and act as “miniature ocean basins”. Fjord settings allow us to study similar geological processes to those that acted on glaciated continental margins but at smaller scales. The variety of sediment inputs (e.g. glacial, fluvioglacial, fluvial, biological) to fjord basins along with relatively high sedimentation rates provides the potential for high-resolution palaeoclimatic and palaeooceanographic records on decadal to centennial timescales.

The aim of this session is to bring together researchers working on both northern and southern high latitudes processes spanning various spatio-temporal scales, to provide a multi-disciplinary picture of polar regions. We welcome submissions focussing on (but not limited to) records of past climatic change, tectonics, oceanography and ecosystems, and the associated links with ice sheets and glacier behaviour, ice-ocean interactions and glacial-marine sedimentary processes. Studies that integrate different datasets, data types, or that marry observations with numerical modelling are also encouraged.

Public information:
Session schedule:

14.00-14.02 Welcome and introduction

14.02-14.10 D3130 | EGU2020-7493 David Hutchinson et al., Arctic closure as a trigger for Atlantic overturning at the Eocene-Oligocene Transition

14.10-14.18 D3131 | EGU2020-7943 Katrien Van Landeghem et al., Relating changes in seabed properties and retreating glacier fronts in West-Antarctic fjords

14.18-14.26 D3135 | EGU2020-12484 Joe Stoner et al., Deriving paleo-perspectives on polar systems: Continued results from the 2012 Sawtooth Lake (Ellesmere Island) and 2015 Petermann (North Greenland) Expeditions

14.26-14.34 D3136 | EGU2020-768 Julia Rieke Hagemann et al., Southern Chilean continent-ocean interaction over the last glacial cycle

14.34-14.42 D3140 | EGU2020-10921 Tom Arne Rydningen et al., New results on the dynamics of the NW part of the Svalbard Ice Sheet during the deglaciation of the Woodfjorden Trough

14.42-14.50 D3142 | EGU2020-12940 Michele Rebesco et al., Multi-proxy analysis of Late Quaternary ODYSSEA Contourite Depositional System (Ross Sea, Antarctica) and the depositional record of contour current and cold, dense waters

14.50-14.58 D3143 | EGU2020-13950 Juliane Müller et al., Deglacial sea ice variability at the continental margin off western Dronning Maud Land

14.58-15.06 D3144 | EGU2020-17953 Jostein Bakke et al., Late glacial and Holocene glacier fluctuations at the Sub-Antarctic Island Kerguelen in the Southern Indian Ocean

15.06-15.14 D3145 | EGU2020-18143 Marie Protin et al., Geological, geochemical and cosmogenic nuclides constraints from the NEEM core basal sediments, Greenland

15.14-15.22 D3147 | EGU2020-19076 Kseniya Mikhailova et al., Glendonites from Mesozoic succession of eastern Barents sea: distribution, genesis and paleoclimatic implications

15.22-15.30 D3148 | EGU2020-19216 Eivind W. N. Støren et al., Reconstruction of Holocene glacier fluctuations at Kongsbreen based on sediments deposited in lake Sarsvatnet, Ossian Sarsfjellet, Svalbard

15.30-15.45 General discussion and outstanding questions

This session aims to place recently observed climate change in a long-term perspective by highlighting the importance of paleoclimate research spanning the past 2000 years.
We invite presentations that provide insights into past climate variability, over decadal to millennial timescales, from different paleoclimate archives (ice cores, marine sediments, terrestrial records, historical archives and more). In particular, we are focussing on quantitative temperature and hydroclimate reconstructions, and reconstructions of large-scale modes of climate variability from local to global scales.This session also encourages presentations on the attribution of past climate variability to external drivers or internal climate processes, data syntheses, model-data comparison exercises, proxy system modelling, and novel approaches to producing multi-proxy climate field reconstructions.

The Ancient Silk Road was one of the most important passages for trans-Eurasia exchange and human migration, which witnessed the rise and fall of ancient civilizations in Central Eurasia. In the central part of the Ancient Silk Road, where the climate condition is extremely dry and the ecosystem is very fragile. The climate and environment changes, especially the water resources change in this area, can significantly influence the spatio-temporal distribution of Ancient Silk Road network, the trans-Eurasia exchange and human migration along the Ancient Silk Road, and the civilization evolution of these ancient cities and towns among the Ancient Silk Road network. This session aims to explore the history of trans-Eurasia exchange, human migration, Ancient Silk Road network spatial change, civilization evolution and climate and environment change, as well as relationship among them in the areas along the Ancient Silk Road. We welcome presentations concerning these issues from multi-disciplinary perspectives, to promote the advancements of research in the field.

Public information:
Authors are kindly asked to upload display material by Sunday, 26th April, 2020, so that there is one week prior to the online chat for viewing the displays.

Program for the Live Chat on 4th May, 2020, 8.30 - 10.15 CEST (14:30–16:15 PM, Beijing)

14:20–14:30 PM, Beijing Sign in and introduction to session

1. D2537, EGU2020-21976（14:30-14:40 PM, Beijing）
Pollen-based quantitative land-cover reconstruction for northern Asia covering the last 40 ka
Xianyong Cao, Fang Tian, Furong Li, Marie-José Gaillard, Natalia Rudaya, Qinghai Xu, and Ulrike Herzschuh
2. D2539, EGU2020-3185（14:40-14:50 PM, Beijing）
An n-alkane-based Holocene climate reconstruction in the Altai Mountains, northern Xinjiang, China
Min Ran
3. D2542, EGU2020-6328（14:50-15:00 PM, Beijing）
Variation of bacterial communities in Muztagh ice core from 1869 to 2000
Yongqin Liu, Tandong Yao, and Baiqing Xu
4. D2549, EGU2020-13015（15:00-15:10 PM, Beijing）
Changes in the hydrodynamic intensity of Bosten Lake and its impact on early human settlement in the northeastern Tarim Basin, eastern Arid Central Asia
Haichao Xie
5. D2550, EGU2020-4601（15:10-15:20 PM, Beijing）
Holocene moisture variations in western arid central Asia inferred from loess records from NE Iran
Qiang Wang, Haitao Wei, Farhad Khormali, Leibin Wang, Haichao Xie, Xin Wang, Wei Huang, Jianhui Chen, and Fahu Chen
6. D2551, EGU2020-3196（15:20-15:30 PM, Beijing）
Holocene moisture variations in the Tianshan Mountains and their geographic coherency in the mid-latitude Eurasia: A synthesis of proxy records
Yunpeng Yang
7. D2553, EGU2020-5067（15:30-15:40 PM, Beijing）
Mid-late Holocene hydroclimate variation in the source region of the Yangtze River revealed by lake sediment records
Xiaohuan Hou, Lina Liu, Zhe Sun, Xianyong Cao, and Juzhi Hou
8. D2554, EGU2020-4965（15:40-15:50 PM, Beijing）
Late Holocene Varve Chronology and High-Resolution Records of Precipitation in the Central Tibetan Plateau
Kejia Ji, Erlei Zhu, Guoqiang Chu, and Juzhi Hou
9. D2555, EGU2020-3874（15:50-16:00 PM, Beijing）
The forced response of Asian Summer Monsoon precipitation during the past 1500 years
Zhiyuan Wang, Jianglin Wang, Jia Jia, and Jian Liu

Discussion and summery（16:00-16:15 PM, Beijing）

While the information, preserved in the records of instrumental measurements, provide an inside view into the history of weather-related extremes of the last 100-150 years or shorter, documentary evidence and the results of natural scientific investigations allow to extend this knowledge several centuries (or millennia) into the past. This concerns, for example those disastrous extremes which were not recorded in the instrumental period, but are known from documentary sources. Compared to palaeo-hydrological investigations of extremes, the papers presented in this session are aimed to provide high-resolution information (with exact dating) based on data derived from documentary evidence, covering a period that does not exceed one-two millennia.
On the one hand, investigations focused on the long-term understanding of variability, changes and shifts in the climatic and/or hydrological regime as well as in the frequency/magnitude of meteorological and hydrological extremes and hazards are welcome. On the other hand, investigations concentrating on one or more great extreme events (extreme cold, heat, floods, droughts etc.) are also invited in the session. Papers discussing the detection of causes of hydrological, meteorological extremes and hazards (environmental, atmospheric/climatic and society-related) in historical times are also addressed and supported to participate in the session. Thus, another important topic of the session is socio-economic responses on extremes or catastrophic events as well as long-term changes, development in cooping weather-related natural hazards. As an integrate part of socio-economic response, the perception and social representation of weather and hydrological hazards and extremes (e.g. floods, droughts) in historical periods are also valuable topics of discussion in the session.
Since this research requires the development of regional chronologies based on good-quality historical sources, besides natural and applied scientists, the active presence and work of historians is of vital importance. The results of historical hydrology investigations and the study of hydro-meteorological extremes in historical times may be utilised in a number of areas such as risk assessment, flood control, hydrological forecasting/predictions, socio-hydrology or in the understanding of the main drivers of hydro-morphological processes.

Interdisciplinary study of the Northeast Atlantic region offers an extraordinary opportunity to advance understanding of interactions and co-dependencies between the solid Earth, ocean, atmosphere, cryosphere and climate. Understanding these issues are of critical importance to Europe and Scandinavia, and they are of global relevance. The unprecedented surge in exploration of the Northeast Atlantic Realm that has unfolded in recent years has delivered major leaps forward in understanding its geological structure, dynamics and development, economic resources and volcanism. Examples include the complexity of the conjugate volcanic rifted margins, contact metamorphism of carbon-rich shales by sill intrusions, producing thermogenic methane, the discovery of widespread continental crust in the ocean, the critical role of the Greenland-Iceland-Faroe bathymetric ridge in influencing ocean circulation between the Arctic and the Atlantic south of Iceland, mapping of gas hydrates and the study of crustal structure beneath the Greenland icecap. Throughout the Cenozoic these factors have influenced ocean and atmosphere composition and circulation, climate change, and the growth, wastage and transport of ice. Detailed understanding of the interdependencies of these phenomena in the past and through time is arguably of critical importance to understanding the current, rapid changes in the natural environment. The goal of this special session is to bring together diverse contributions drawing on all the above disciplines in order to identify potentially fertile areas for broad, cross-disciplinary study of the Northeast Atlantic Realm moving forward.

In recent decades, quantitative methods have become increasingly important in the field of palaeoenvironmental, palaeoclimatic and palaeohydrological reconstruction, due to the need for comparison between different records and to provide boundary conditions for computational modelling. Continental environmental archives (e.g. speleothems, lake sediments, land snails, rivers, or peatlands) are often highly temporally resolved (subdecadal to seasonal) and may provide more direct information about atmospheric and hydrological processes than marine archives. The wide variety of archive types available on land also allows for intercomparison and ground-truthing of results from different techniques and proxies, and multi-proxy reconstructions from the same archive can disentangle local and supra-regional environmental conditions. This approach is particularly useful for the reconstruction of hydrological dynamics, which are challenging to reconstruct due to their high spatial variability, signal buffering, nonlinearities and uncertainties in the response of palaeoclimate archives and proxies. For example, climate-independent factors such as land cover change can affect the local to regional water availability recorded in proxies.

This session aims to highlight recent advances in the use of innovative and quantitative proxies to reconstruct past environmental change on land. We present studies of various continental archives, including but not limited to carbonates (caves, palaeosols, snails), sediments (lakes, peatlands, rivers, alluvial fans), and biological proxies (tree rings, fossil assemblages, biomarkers). We particularly include studies involving the calibration of physical and chemical proxies that incorporate modern transfer functions, forward modeling and/or geochemical modeling to predict proxy signals, and quantitative estimates of past temperature and palaeohydrological dynamics. We also include reconstructions of temperature and hydrologic variability over large spatial scales and palaeoclimate data assimilation. This session will provide a forum for discussing recent innovations and future directions in the development of terrestrial palaeoenvironmental proxies on seasonal to multi-millennial timescales.

Public information:
Please note that the order and number of presentations has been changed as some authors could not attend under the circumstances, or have parallel duties.

Authors are kindly asked to upload display material by Friday, 1st May, 2020 so that there is the weekend prior to the online chat for viewing the displays.

Our Programme for the Live Chat on 4th May, 2020, 10.45 - 12.30 CET

10.45 - 10.50 Sign in and introduction to session

10.50 - 10.56
D3703 | EGU2020-12712
Changes in biogeochemistry recorded in the Lisan formation and the Dead Sea Basin
Alexandra Turchyn, Harold Bradbury, and Adi Torfstein

10.56 - 11.02
D3707 | EGU2020-21994
Holocene climate in Northern Urals (Komi Republic, Russia): a multiproxy approach based on pollen and brGDGTs
Chéïma Barhoumi, Sébastien Joannin, Adam A. Ali, Guillemette Ménot, Yulia Golubeva, Dmitri Subetto, Alexander Kryshen, Igor Drobyshev, and Odile Peyron

11.02 - 11.08
D3708 | EGU2020-1150
Primary production in a kettle lake (Canada) was not driven by effective moisture over the last ~900 years
Rebecca Doyle, Zijun Liu, Jacob Walker, Ryan Hladyniuk, Katrina Moser, and Fred Longstaffe

11.08 - 11.14
D3731 | EGU2020-18227
Reconstructing past hydrology from drift sand archives: possibilities and limitations
Koen Beerten, Wouter van der Meer, Koen Hebinck, Miel Schurmans, and Jan Bastiaens

11.14 - 11.20
D3709 | EGU2020-19247
Global hydroclimate of the Last Interglacial: precipitation, river discharge, floods
Paolo Scussolini and the Last Interglacial Floods

11.20 - 11.26
D3705 | EGU2020-18100
A 1,600 year record of paleoseasonality from the neotropics of Central America and its implications for rainfall predictability in agricultural societies
Keith Prufer, Sebastian Breitenbach, James Baldini, Tobias Braun, Erin Ray, Lisa Baldini, Victor Polyak, Franziska Lechleitner, Norbert Marwan, Douglas Kennett, and Yemane Asmerom


D3725 | EGU2020-11105
CANCELLED :-(
Nehme et al.: Speleothem record from Pentadactylos cave (Cyprus): high resolution insight into climatic variations during MIS 6 and MIS 5

11.26 - 11.32
D3723 | EGU2020-2397
Application of novel trace analysis methods for lignin and levoglucosan in flowstone samples from New Zealand during the Holocene
Anja Beschnitt and Thorsten Hoffmann

11.32 - 11.38
D3724 | EGU2020-2413
Trace analysis of levoglucosan and lignin-phenols in speleothems by HILIC-UHPLC-ESI-HRMS: A new method
Julia Homann, Anja Beschnitt, and Thorsten Hoffmann

11.38 - 11.44
D3726 | EGU2020-16898
Rainfall seasonality changes in northern India across the 4.2 ka event
Alena Giesche, Sebastian F.M. Breitenbach, Norbert Marwan, Adam Hartland, Birgit Plessen, Jess F. Adkins, Gerald H. Haug, Amanda French, Cameron A. Petrie, and David A. Hodell

11.44 - 11.50
D3720 | EGU2020-992
Structural ecosystem change in Holocene chironomid assemblages
Roseanna Mayfield, Peter Langdon, John Dearing, Patrick Doncaster, and Rong Wang

11.50 - 11.56
D3711 | EGU2020-5311
Paleoclimatic reconstruction studies in lake sediments: major proxies, technical evolution and database
Paula Bianchini, Elder Yokoyama, and Luciana Prado

11.56 - 12.02
D3715 | EGU2020-12592
Biomarker (brGDGT) degradation and production in lacustrine surface sediments: Implications for paleoclimate reconstructions
Cindy De Jonge, Annika Fiskal, Xingguo Han, and Mark Lever

12.02 - 12.08
D3721 | EGU2020-8457
A theory of palaeoclimate reconstruction
Mengmeng Liu, Iain Colin Prentice, Cajo ter Braak, and Sandy Harrison

12.08 - 12.14
D3729 | EGU2020-4240
What we talk about when we talk about seasonality?
Ola Kwiecien

12.14 - 12.20
D3732 | EGU2020-4887
Reconstructions of past sediment and water discharges from fluvial-fill terraces in the southern Central Andes of NW Argentina
Stefanie Tofelde, Taylor Schildgen, Andrew Wickert, Manfred Strecker, and Ricardo Alonso

12.20 - 12.30 Summary of session

Tree rings are one of nature’s most versatile archives, providing insight into past environmental conditions at annual and intra-annual resolution and from local to global scales. Besides being valued proxies for historical climate, tree rings are also important indicators of plant physiological responses to changing environments and of long-term ecological processes. In this broad context we welcome contributions using one or more of the following approaches to either study the impact of environmental change on the growth and physiology of trees and forest ecosystems, or to assess and reconstruct past environmental change: (i) traditional dendrochronological methods including studies based on tree-ring width and density, (ii) stable isotopes in tree rings and related plant compounds, (iii) dendrochemistry, (iv) quantitative wood anatomy, (v) ecophysiological data analyses, and (vi) mechanistic modelling, all across temporal and spatial scales.

In an era of science that uses numerical models to better understand physical processes occurring on Earth, there is an increasing demand for robust empirical datasets to constrain these simulations. Generating robust datasets, especially data sets that express stratigraphic positions of sedimentary deposits as ages, often involves the use of multiple, independent geochronological techniques (e.g. different kinds of radioisotopic dating, magneto-, bio-, cyclostratigraphy and sedimentologic relationships along the succesion). The integration of these different kinds of geochronological information often poses challenges.

Age-depth models are the ultimate result of the integration of different geochronological techniques, and range from linear interpolation to more complex Bayesian techniques. We will introduce several modelling concepts and their application in a range of paleoenvironmental and paleoclimatic records. The Short Course will provide an introduction to the field of (Bayesian) age-depth models and will highlight the assumptions, benefits and limitations of different model approaches. It will prepare participants for independent application of suitable age-depth models to their data.

Public information:
We are planning on holding a 2-day course in Bremen this autumn, please keep an eye on the following website
https://www.marum.de/Ausbildung-Karriere/Courses-2020.html
and/or ask Christian.Zeeden@leibniz-liag.de to be informed on news regarding this.

Speleothems and continental carbonates (e.g. travertines, anthropogenic travertines, subglacial and cryogenic carbonates) are important continental archives, which can provide precisely dated, high-resolution records of past environmental and climate changes across all climate zones. This session aims to showcase the most recent developments and findings related to analytical developments, process understanding, and new records on annual, seasonal, sub- and orbital timescales. In this session, contributions are particularly welcome on: (1) monitoring of soil and cave systems in order to improve understanding of the speleothem and continental carbonate archive; (2) high-resolution orbital and sub-orbital palaeoclimate reconstructions on Quaternary timescales and longer; (3) new and novel techniques as well as methodological developments as applied to speleothems and continental carbonates; (4) interdisciplinary approaches that combine speleothem and/or continental carbonate records with other proxy archives and/or modelling.

Public information:
Authors are kindly asked to upload display material by Sunday, 26th April, 2020 so that there is one week prior to the online chat for viewing the displays.

Programme for the Live Chat on 4th May, 2020, 8.30 - 10.15 CET

8.30 - 8.35: Sign in and introduction to session

8.35 - 8.45
D3733 | EGU2020-1686
Insights into recharge processes and speleothem proxy archives from long-term monitoring networks of cave drip water hydrology
Andy Baker, Pauline Treble, Andreas Hartmann, Mark Cuthbert, Monika Markowska, Romane Berthelin, Carol Tadros, Matthias Leopold, and Stuart Hankin

8.45 - 8.55
D3735 | EGU2020-140
A long continuous palaeoclimate-palaeoenvironmental record of the last glacial period from southern Italy and implications for the coexistence of Anatomically Modern Humans and Neanderthals
Andrea Columbu, Veronica Chiarini, Christoph Spötl, Jo De Waele, Stefano Benazzi, John Hellstrom, and Hai Cheng

8.55 - 9.05
D3736 | EGU2020-4800
History of Late Pleistocene Permafrost in Southern Ural revealed by studies of speleothems and cave sediments
Yuri Dublyansky, Gabriella Koltai, Denis Scholz, Michael Meyer, Luke Gliganic, Olga Kadebskaya, Hai Cheng, and Christoph Spötl

9.05 - 9.15
D3739 | EGU2020-1054
Using hierarchical dynamic time warping to synchronize age-uncertain (proxy) time series
Yuval Burstyn and Asaf Gazit

9.15 - 9.25
D3741 | EGU2020-11089
Monitoring activities in several caves along a transect stretching from the Adriatic Sea to the Aggtelek Karst (NE-Hungary): trace element and stable isotopic compositions of drip waters and cave carbonates
György Czuppon, Attila Demény, Neven Bocic, Nenad Buzjak, Krisztina Kármán, Zsófia Kovács, Szabolcs Leél-Össy, Szilárd John, Mihály Óvári, and Emese Bottyán

9.25 - 9.35
D3744 | EGU2020-7466
Understanding the deglacial relationship between carbon isotopes and temperature in stalagmites from Western Europe
Franziska A. Lechleitner, Christopher C. Day, Micah Wilhelm, Negar Haghipour, Oliver Kost, Gideon M. Henderson, and Heather M. Stoll

9.35 - 9.45
D3751 | EGU2020-19608
Climate driven mobility of the early humans in SW Asia: Preliminary evidence from Iranian Stalagmites
Arash Sharifi, Ali Pourmand, Mehterian Sevag, Peter Swart, Larry Peterson, and Hamid A. K. Lahijani

9.45 - 9.55
D3752 | EGU2020-18326
The Maya Terminal Classic Drought replicated in two stalagmites from Columnas Cave, NW Yucatán
Daniel James, Sebastian Breitenbach, Hai Cheng, Adam Hartland, Ian Orland, Mark Brenner, Jason Curtis, Christina Gallup, Soenke Szidat, John Nicolson, James Rolfe, Andrew Mason, Gideon Henderson, and David Hodell

9.55 - 10.05
D3753 | EGU2020-10343
Holocene hydroclimate of the Volga Basin recorded in speleothems from the Central and Southern Ural Mountains, Russia
Jonathan Baker, Yuri Dublyansky, Olga Kadebskaya, Denis Scholz, Gabriella Koltai, Hanying Li, Jingyao Zhao, Christoph Spötl, and Hai Cheng

10.05 - 10.15 - Open Discussion

Inspired by the classic textbook “Tracers in the Sea” (Broecker and Peng, 1982) for the session’s name, we invite contributions bearing on chemical and isotopic tracers used in paleoceanography. Proxies are the backbone of paleoceanography and undergo frequent new developments. New analytical techniques and applications allow for the investigation of new proxy systems as well as the exploration of existing proxies with new substrates or more challenging sample sizes. Growing datasets have led, and are leading, to comprehensive compilations, proxy inter-comparisons, and quantitative tests of paleoceanographic model simulations. For this session, we invite presentations on both (i) modern calibrations and downcore applications, (ii) single and multiple proxies, and (iii) proxy measurements and modeling. Despite their wide applications, paleoceanographic proxies suffer generally from significant limitations. As illustrated in a famous figure by the late H. Elderfield, our confidence in a proxy goes from an optimism phase, to a pessimism phase, and eventually to a realism phase. In this spirit, both “good” and “bad” news during the development and application of proxies are welcome.

Soil-forming processes can be observed at various spatial and temporal scales, including molecular - microscopic - pedon - landscape scales, and a similarly wide range of temporal scales. They are influenced not only by the “classical five” soil-forming factors, but also by the factor “humans”. This holds true not only for the industrial period and urbanized areas, but also for palaeopedological and archaeological contexts.
In this session, we seek abstracts on all of these aspects of “soils as records in time and space”:
- soil processes proceeding at different scales, incl. interactions across scales (both spatial and temporal)
- human-induced soil changes (incl. mechanical and chemical changes, as well as the introduction of artificial parent materials)
- advances in understanding weathering mechanisms and mineralogical changes in time and space
- linkages of spatial patterns and processes in soil landscapes over time
- processes taking place on short time scales, thereby contributing to long-term soil changes
- aeolian inputs to soils, implications for soil genesis and ecologically relevant soil properties
- palaeosols and geomorphic features as records of former environments and human activity
- use of soil classification and soil maps, and possibly links to digital soil mapping and novel soil survey techniques such as proximal sensing technologies and detailed digital elevation models.

(Bio)minerals, in particular carbonates (but also others e.g. phosphates), play an essential role in shaping our understanding of the evolution of life and the Earth System, and constitute one of the most important archives of past climatic and environmental conditions. Geochemical, petrographic or crystallographic approaches have yielded new insights into the physico-chemical conditions governing their formation, including through biomineralisation pathways. These capture vital information about the environment and fluid chemistry during precipitation in the form of their specific elemental or isotopic signatures, mineralogies or micromorphologies. Over the past decades, a refined understanding of both biogenic as well as abiotic carbonates and other mineral archives, together with the development of new analytical methods and palaeo-proxies, has led to numerous breakthroughs in palaeoclimate research. However, the quality and reliability of the climatic and environmental information we extract from these records depends, critically, on careful proxy calibrations and the evaluation of secondary controls such as kinetic or vital effects and diagenetic influences. This session seeks contributions from sedimentology, geochemistry, (palaeo)biology, and mineralogy that utilise carbonate or other relevant (bio)minerals to improve our understanding of past environmental conditions over a broad range of timescales, including (but not limited to) microbialites, mollusc shells, coral skeletons or foraminifera. We welcome experimental or theoretical studies dealing with culturing of calcifying organisms, synthetic mineral precipitation, transformation or alteration processes, elemental partitioning or isotopic fractionation (to give but a few examples). The aim of this session is to synthesize recent progress on the investigation as well as application of these important archives, and to showcase methodological advances that will help us to build a more comprehensive understanding of past global changes.

Interactions between tectonics, climate and biotic evolution are ideally expressed in Asian orogenies. The ongoing surge of international research on Asian regions enables to better constrain paleoenvironmental changes and biotic evolutions as well as their potential driving mechanisms such as global climate, the India-Asia collision and the tectonic growth of the Himalayan-Tibetan and other Asian orogens. Together these efforts allow for a comprehensive paleogeographic and paleoenvironmental reconstructions that enable to constrain climate modelling experiments which permit validation of hypotheses on potential interactions.
The goal of this session is to assemble research efforts that constrain Asian tectonic, climate (monsoons, westerlies, aridification), land-sea distribution, surface processes or paleobiogeographic evolution at various timescales. We invite contributions from any discipline aiming for this goal including broadly integrated stratigraphy, tectonic, biogeology, climate modelling, geodynamic, oceanography, geochemistry or petrology.

Today the Indo-Pacific Warm Pool (IPWP) represents a crucial part of the global thermohaline circulation by acting as a low latitude heat source for the polar regions. The IPWP’s importance in deciphering past and future coupled ocean-atmosphere dynamics is highlighted by the complex interactions between this region and globally significant climatic systems like the Australasian Monsoon, Intertropical Convergence Zone (ITCZ), El Niño Southern Oscillation (ENSO) and the Indian Ocean Dipole (IOD).

This session will explore the IPWP’s role in global climate change and its emergence as a biogeographic diversity hot spot from the geological past to the present. We invite submissions on a broad range of topics in sedimentology, palaeontology, paleoclimatology/-oceanography, and data-model comparisons to assemble a comprehensive view of the Cenozoic evolution of the entire Indo-Pacific Region. We encourage submissions stratigraphically synthesising marine-terrestrial multi-proxy archives, and those investigating teleconnections between the IPWP, zonal (ENSO/IOD), and high latitude processes. Finally, this session will examine how the long-term evolution of the global monsoons and the ITCZ affected feedbacks between IPWP, Australasian hydroclimate and tectonic/weathering processes.