GLOBAL and LOCAL Challenges facing the Environment
Overview – Students will learn about a variety of different environmental challenges some connected to previous instruction and some that may be new to them.
Energy (Natural Resource) Usage – Global Footprint
How many Earth’s would be needed? Students should revisit the ecological footprint calculator used in Unit 3- Climate Change. How does US energy use compare to other countries energy usage? |
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Biodiversity Loss
Extinctions are a regular occurrence over the course of geologic time. But catastrophic events in which many species go extinct over brief periods of time are rare. When our planet loses more than 70% of its species within a relatively short geological time interval, scientists refer to these cataclysmic losses as mass extinctions. In the past 540 million years alone, scientists estimate that there have been at least five such mass extinction events. Many experts warn that a sixth mass extinction may be on our doorstep, triggered by human activities and a rapidly growing human population that has destroyed habitats and ecosystems around the world. Today, we are seeing massively accelerated extinction rates that exceed normal extinction rates by a factor of 12. Experts estimate that at the current rate, 75% of our species will disappear in less than 200 years. Species extinctions are nearly always preceded by high regional population declines. In this study, researchers measured species population declines on a global scale that may contribute to the sixth mass extinction. The figure shows the results of a study examining population trends for 27,600 land vertebrate species from 1900 to 2015. The researchers found that 32% of these species, many of which are mammals and birds, are currently in decline. The researchers argue that aggressive species and habitat conservation within the next couple of decades are the only ways to avoid a catastrophic sixth mass extinction. (from Explore Extinctions Published October 2017 www.BioInteractive.org)
Extinctions are a regular occurrence over the course of geologic time. But catastrophic events in which many species go extinct over brief periods of time are rare. When our planet loses more than 70% of its species within a relatively short geological time interval, scientists refer to these cataclysmic losses as mass extinctions. In the past 540 million years alone, scientists estimate that there have been at least five such mass extinction events. Many experts warn that a sixth mass extinction may be on our doorstep, triggered by human activities and a rapidly growing human population that has destroyed habitats and ecosystems around the world. Today, we are seeing massively accelerated extinction rates that exceed normal extinction rates by a factor of 12. Experts estimate that at the current rate, 75% of our species will disappear in less than 200 years. Species extinctions are nearly always preceded by high regional population declines. In this study, researchers measured species population declines on a global scale that may contribute to the sixth mass extinction. The figure shows the results of a study examining population trends for 27,600 land vertebrate species from 1900 to 2015. The researchers found that 32% of these species, many of which are mammals and birds, are currently in decline. The researchers argue that aggressive species and habitat conservation within the next couple of decades are the only ways to avoid a catastrophic sixth mass extinction. (from Explore Extinctions Published October 2017 www.BioInteractive.org)