Dust and climate changes: "Dust is simply everywhere!"

09.12.2019

Geologist Gabor Ujvari works as a Senior Postdoc and Lise Meitner Research Fellow at the Department of Lithospheric Research of the University of Vienna. The hungarian scientist is interested in the composition of mineral dust and specializes in the novel isotope geochemical tracing of Greenland ice core dust.

One of Gabor Ujvari‘s greatest dreams is to travel to the origin of the samples of his research project: the Central Greenland ice sheet. “Unfortunately I haven't had the opportunity to travel there yet, but I'd really love to”, the hungarian geologist says.

Though Greenland may be far away, the results of the scientists work are closely related to a topic that affects the entire planet: contemporary climate change. “Climate change affects or will affect large-scale patterns of atmospheric circulation on a global scale, influencing and controlling both temperatures and precipitation”, he says. “Atmospheric simulations may predict these processes, but it is imperative to test the performance of such models under climatic conditions some thousands of years ago in the geological past when that were profoundly different from those of the present day. And here is where my research work starts.”

Archives of palaeoclimatic change

Greenland ice cores are archives of palaeoclimatic change. “Constraining the origin of dust and examining the impurity content, helps to better understand the effects of climatic changes on land, precipitation and vegetation as well as to validate atmospheric circulation models under glacial climate conditions”, Ujvari says.

During his two years as a Lise Meitner Fellowship he first wants to gain a better knowledge of the hafnium isotopic composition of dust and understand this system in general and then, in a second step, apply his knowledge on the Greenland ice core samples. “For the moment, this means really time-consuming and tedious work in laboratories”, Ujvari describes his everyday work – which already starts with office tasks and reviews on his daily morning ride on the train from Sopron, where he lives, to Vienna.

The ice cores the scientist works with are stored in Denmark, at the Niels Bohr Institute in Copenhagen, with which he has been collaborating since his work as a Senior Researcher at the Danish Technical University in 2017. “Besides that also the Technical University Graz, a researcher from the University of Uppsala and the University of Paris, which produces fine aerosols from my sediment samples in its atmospheric chambers, are involved in the project”, he adds.

From glacial dust deposits in Europe ...

Ujvari's work with dust started ten years ago, when he stayed as a Fulbright Research Fellow at the School of Earth and Environmental Sciences of Washington State University. “My early work focused on glacial dust deposits in Europe, also known as Löss, which is widespread as well here in Austria. It was then, in the USA, that I realized I should pursue this.”

Gabor Ujvari‘s work on dust from Greenland ice cores started with a pilot study at the Research Centre for Astronomy and Earth Sciences of the Hungarian Academy of Sciences, where he has a permanent position. His project partner then was Professor Urs Klötzli from the Department of Lithospheric Research of the University of Vienna, with whom he started to collaborate in 2010 and who is now his Supervisor.

... to Greenland and the role of dust in the atmosphere

What is so interesting about dust that he chose this as his specialist topic? “Dust is simply everywhere!”, he says. “The role it plays in the atmosphere is pretty interesting, because it has many direct and indirect effects on climate.” For example, it provides nutrients to different ecosystems in the ocean: “If you add dust with a high iron content to specific ecosystems, this can cause phytoplankton to bloom, and phytoplankton consumes huge amounts of CO2, so this can drop the CO2 content of the atmosphere. Actually, there is a significant body of research on dust with many ongoing research projects, but we still need a better understanding of the system.” (isa)

  • Title of project: Novel isotope geochemical tracing of Greenland ice core dust
  • Funding authority: FWF – Der Wissenschaftsfonds
  • Number of project (FWF): M2503-N29
  • Applicants: Gabor Ujvari, PhD and Prof. Dr. Urs Klötzli
  • Duration: 24 months - 1.10.2018 - 30.09.2020
  • Project description: Remarkable climatic/environmental changes (interglacial warming/glacial cooling) occurred some thousands of years ago in the geological past, which altered atmospheric circulation and changed dust emissions significantly from time to time due to hydrological and vegetation changes. Mineral dust emitted from the continents loaded the atmosphere and subsequently accumulated on the Greenland ice sheet after long-range (several thousands of km) transport. Impurity concentration variations measured in central Greenland ice cores provide a record of past climatic changes and activities of dust emission centers, but it is equally important to identify which sources contributed dust to the ice sheet and how their role may have changed. The project attempts to identify these dust sources in the present research using novel approaches (Hf isotopic fingerprinting in combination with Sr and Nd isotopic fingerprinting).

Gabor Ujvari lives in Sopron, but works as a Senior Post Doc and Lise Meitner Research Fellow at the Department of Lithospheric Research of the University of Vienna. The Geologist is interested in the composition of mineral dust and specializes in the novel isotope geochemical tracing of Greenland ice core dust.

During his two years as a Lise Meitner Fellowship he concentrates on the hafnium isotopic composition of dust and on Greenland ice core samples.

Photo: The North Greenland Eemian Ice Drilling (NEEM) project camp in Greenland. © NEEM ice core drilling project, www.neem.ku.dk

Drill head for drilling deep ice cores. © Photo: NEEM ice core drilling project, www.neem.ku.dk., Olivia Maselli