Subglacial lakes, hidden under the Antarctic ice sheets, constitute the opportunity to study the last 20,000 years of evolution of the Antarctica's climate in much more detail. This is one of the main conclusions of the chapter ‘Holocene environmental changes inferred from sediments of Antarctic lakes’, written by Santiago Giralt, from Geociencias Barcelona – CSIC (GEO3BCN – CSIC), and other researchers, including Armand Hernández, researcher at the institute until the end of 2019. The chapter is part of the book entitled ‘Past Antarctica. Paleoclimatology and climate change’, edited by Elsevier, which gathers contributions from different perspectives on the evolution the continent has undergone.
“It was thought that every Antarctic lake had been formed as a consequence of the last deglaciation process, which started 20,000 years ago”, says Giralt. Nevertheless, the researcher explains that “many of the subglacial found present enough evidences to assume that they are much older than the surface ones”.
The chapter written by Giralt is focus on the study of lakes sedimentary registers located in the Antarctic periphery. The aim is to give a holistic vision of the climatic and environmental evolution of the continent during the last 11,700 years. According to Giralt, “this paper is the last major review of all recent literature about this topic”.
This part of the book reviews environmental evolution of Antarctica during Holocene, a period with a complex temporal and spatial pattern, possibly related to the difficulties in building robust chronological frameworks for sedimentary records and the irregular geographical distribution of the studied cores.
The 'Past Antarctica. Paleoclimatology and climate change' was coedited by Marc Oliva, from Geography department of the Barcelona University, and by Jesús Ruiz Fernández, from the Geography department of the Oviedo University. This volume, written by researchers from different fields, is composed by 15 chapters which rebuilds the past of the continent synthetizing the existing knowledge in different disciplines such as geology, climatology, biology and history.
According to Giralt, the book emphasizes the importance of understanding every physics, geological, biological and chemical process that happen in Antarctica, since any change may affect significantly each other. “This holistic vision can only be reached from an interdisciplinary perspective. This book highlights this point”, says the researcher.
Fight against the climate change knowing the Antarctica's past
The GEO3BCN-CSIC researcher highlights that the historic knowledge of the “big climate regulators of the Earth”, as Antarctica and Artic, is very useful to tackle and prevent the climate change. “Understanding what is happening in both poles and how they are going to change due to the increase of the greenhouse gases in the near future is essential to know what is happening in the rest of the planet and its possible consequences”, explains Giralt. “It is not possible to design and implement measures to mitigate the negative impacts of the current global change if there is not a deep understanding of how the climate system works as a whole”, he adds.
Regarding the future research, Giralt mentions the research work that he is currently carrying out in Greenland along with other researchers: “This study aims to understand the most recent climate evolution and how the climate changes that are affecting this territory are affecting us”.
In this sense, Giralt notes that Spain is member of the Arctic Council as an observer from 2006 and is able to participate in the periodical meetings, to give scientific advise, to plan research projects in the Artic and to fund. “The changes that are happening in the Arctic are affecting significantly our latitudes”, points out the researcher.
However, Giralt refers the technical and logistical difficulties as a result of working in extreme environments. “Research in the polar zones requires a large amount of human and financial resources that are not always easy to find and dispose of”, he says.
Giralt, S., Hernández, A., Pla-Rabes, S., Antoniades, D., Toro, M., Granados, I., & Oliva, M. (2020). Chapter 3 - Holocene environmental changes inferred from Antarctic lake sediments (M. Oliva & J. B. T.-P. A. Ruiz-Fernández (eds.); pp. 51–66). Academic Press. https://doi.org/https://doi.org/10.1016/B978-0-12-817925-3.00003-3
Oliva, M., & Ruiz-Fernández, J. B. T.- P. A. (Eds.). (2020). Past Antarctica: Paleoclimatology and Climate Change. Academic Press. p. 326. ISBN: 978-0-12-817925-3. https://doi.org/10.1016/C2018-0-02237-9