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Sustainability in the Space Industry
Published in Mark W. McElroy, The Space Industry of the Future, 2023
Sadly, the planet is in the midst of a mass extinction event. Species are going extinct now at a rate not seen since the end of the dinosaurs 65 million years ago. The current extinction event is caused by human activity in the form of habitat destruction, pollution, overhunting/fishing, clear-cutting, and introduction of invasive species. One estimate predicts 50% of existing species will be gone by 2100 [234]. The planetary life support system consists of geological, atmospheric, oceanic, and biological components. It is what yields things like clean water, breathable air, and food (recall discussion in Chapter 4 on ecosystem services). If 50% of the biological diversity is removed from the system, what are the implications to these life support functions that everyone takes for granted? The planetary biological system is so big and complicated that the answer is difficult to predict, but the stakes could not be higher.
An introduction to the world ocean
Published in Mark Zacharias, Jeff Ardron, Marine Policy, 2019
There is no doubt that the earth’s climate has changed throughout history and that cyclical changes transpired long before humans dominated the planet. Global climate changes have been responsible for mass extinctions in the past and will likely result in future extinction events. During the Quaternary period, sea levels deviated as much as 85m, which inhibited the evolution of established marine communities in coastal and shelf environments. Unquestionably, humans have impacted global temperatures; since the 1980s, there has been considerable debate on differentiating the natural and anthropogenic contributions to climate change. Recent evidence, however, concludes that climate change since the 1900s is human-induced, and it is estimated that the oceans have lost 2 per cent of their oxygen since 1960. (Gilbert, 2017)
The Biosphere
Published in John C. Ayers, Sustainability, 2017
How do current extinction rates compare to those in Earth’s past? Extinction events are characterized by their magnitude (percentage of species that go extinct) and rate (usually extinctions per million species-years). Mass extinction events are defined as times when the rate of extinction exceeded the rate of creation of new species long enough to decrease the global number of species by 75% or more (Barnosky et al. 2011). Five mass extinction events in the last 540 million years are recorded in Earth’s fossil record, and these events typically lasted less than two million years. Current extinction rates are higher than during those five mass extinction events (Barnosky et al. 2011). These elevated rates have only persisted over a few hundred years, causing the extinction of several percent of identified species. However, if these elevated rates persist or increase, more than 75% of species could go extinct in as little as three centuries.
Mid-Phanerozoic microbialite forms and associated facies in the northern Perth Basin, Western Australia, and their relationship to the end-Permian mass extinction
Published in Australian Journal of Earth Sciences, 2022
L. J. Olden, M. Barham, J. Cunneen, H. K. H. Olierook, E. Suosaari, G. C. Smith
Throughout geological time there have been multiple biotic crises, with at least five recorded major mass extinction events in the Phanerozoic (Hallam & Wignall, 1997). The most catastrophic, the end-Permian mass extinction (EPME), occurred at ca 252 Ma associated with the emplacement of the Siberian Traps large igneous province (Burgess et al., 2014; Keller, 2005; Wignall, 2007). Microbialites are frequently reported following this ecological crisis (Adachi et al., 2017; Ezaki et al., 2003; Fang, Chen, Kershaw, Li et al., 2017; Fang, Chen, Kershaw, Yang, 2017; Huang et al., 2018; Kershaw et al., 2007; Lehrmann et al., 2003; Luo et al., 2016; Shen et al., 2012; Wu et al., 2017). The majority of stromatolite studies on this time period focused on carbonate ramp and shallow marine settings as these environments are particularly susceptible to extinction-related phenomena, thereby reducing ecological competition and promoting microbialite development. However, other depositional environments with microbial influence remain less well characterised.