4 Jul 2022

Talk 6/7-2022: Dahl colloquium at IPM, Hamburg University

July 6th, 2022 @ 17:15. Institut für Pflanzen und Mikrobiologie (IPM) is at Ohnhorststr. 18 in Klein Flottbek, a suburb of Hamburg. Tais will give a lecture for the Institute for Plants and Microbiology (IPM) at Hamburg University entitled: “Atmospheric oxygenation and climatic cooling during the early colonization of the terrestrial environment by plants”. The presentation will […]

5 May 2022

Telling actual time in the rock record

We have discovered a new method to tell time in the Geological record, using core scanning XRF analyses, which we have now applied to Cambrian and Ordovician rocks to refine the Geological Time Scale. The study, led by my PhD student Zhengfu Zhao, is now published in Nature Communications. The new method was first discovered […]

14 Oct 2021

Tais is pitching a Science Slam in the Planetarium

On November 19, the Danish rapper Per Vers will orchestrate Science Slam in the Tycho Brahe Planetarium. The program is found here https://planetarium.dk/program/science-slam-faa-toptunet-din-viden-om-universet/. Tais will give a 7 minutes pitch from his research

23 Apr 2021

EarthTalks at GEOCENTER Denmark

The Section for Geobiology at GLOBE has helped organizing the spring season of EarthTalks 2021, and we welcome interested students and researchers to participate over Zoom (link below). The talks will not be recorded. Earth Talks Lecture Series – Spring 2021 Friday afternoons 14:00-15:00 DK time (sharp) 23/4 – Prof. Sigur∂ur Gislason, University of Iceland The […]

28 Mar 2021

Did land plants alter erosion rates on Earth?

A discussion arises from the recent review article in Chemical Geology, where Tais W. Dahl and Susanne Arens concluded that land plants did not forever increase the physical weathering rates of the continental crust. This conclusion was reached from the records of preserved sediment rock volume and the timing of plant-assisted weathering as recorded in […]

27 Jan 2021

The Carlsberg foundation supports field work in Siberia

The Carlsberg Foundation is sponsoring field work led by Tais W. Dahl to Arctic Siberia, where an important climate catastrophe is recorded in marine sedimentary rocks. The expedition will bring back data and samples deposited in the oceans during a climate event that caused sulfidic anoxia to suddenly expand in warming oceans and wipe out […]

12 Oct 2020

Press release: Early animals had a shorter day

In a brief story published in Danish on Videnskab.dk, Aske L. Sørensen and Tais W. Dahl explain one of the consequences of their latest EPSL paper: Earth was spinning faster 500 million years ago. The scientific paper entitled “Astronomically forced climate change in the Late Cambrian” documents Milankovitch-cycles in two drill cores through the Alum […]

18 Apr 2020

New GCA paper: Volcanic eruptions triggered repeated marine anoxia and reveal global-scale feedbacks during the Permian-Triassic mass extinction 250 million yeers ago

The largest animal extinction event in recorded history occurred 251 Ma at the Permian-Triassic boundary coinciding with expansive marine anoxia. In a new study, led by postdoc Feifei Zhang, of a greatly expanded dolomite section from the Carnic Alps, Austria, marine anoxia is found to have expanded in two pulses separated by ~100,000 years. Global […]

22 Oct 2019

Forskerzonen: Mystery about animals in ancient anoxic oceans resolved

The newly discovered ocean ventilation events in the 500 million year old Alum shale ocean is described in Danish on Forskerzonen: Videnskab.dk 

12 Sep 2019

Tracking the global dynamics of Earth’s oxygen and biological production in deep time

In an article published online in PNAS Tuesday Sep 10th, we have demonstrated how a combination of metal isotope analyses in marine sedimentary rocks can constrain the global scale feedbacks between atmospheric oxygen, seafloor oxygenation, and marine biological production. The relationship between O2 and animal life turns out to be more entangled than first thought. […]