How bad is Ocean Warming caused by anthropogenic climate change?
To answer my question, the effects of the current rise in temperatures of our oceans is worse than you or I could have imagined. It’s so bad that it may take thousands of years for ocean life to recover. That’s a recovery time measured in millennia, for those who prefer polysyllabic Latinate words:
A study has found that it might take thousands of years for the ocean to recover from climate change. Researchers studied more than 5,400 fossils from a 30-foot-long core sample taken from the Pacific Ocean floor near Santa Barbara, California, and found that it can take millennia for ocean ecosystems to recover after periods of deoxygenation and warming waters. […] “In this study, we used the past to forecast the future,” Peter Roopnarine, curator of invertebrate zoology and geology at the California Academy of Sciences and co-author of the study, said in a statement. “We don’t want to hear that ecosystems need thousands of years to recover from disruption, but it’s critical that we understand the global need to combat modern climate impacts.”
Here is what the article posted at Science News regarding this research study has to say about its importance to our understanding of the impacts of global warming on Ocean ecosystems and biodiversity:
A 30-foot-long core sample of Pacific Ocean seafloor is changing what we know about ocean resiliency in the face of rapidly changing climate. A new study reports that marine ecosystems can take thousands, rather than hundreds, of years to recover from climate-related upheavals. The study’s authors–including Peter Roopnarine, PhD, of the California Academy of Sciences–analyzed thousands of invertebrate fossils to show that ecosystem recovery from climate change and seawater deoxygenation might take place on a millennial scale. The revolutionary study is the first of its kind, and is published today in the Early Edition of the journal PNAS.
The published study which looked at the fossil record from roughly 16,000 years ago until 3,400 years ago, a period that includes a significant period of time during the current interglacial period (the Holocene) can be found here: Response of seafloor ecosystems to abrupt global climate change. From the Abstract:
Anthropogenic climate change is predicted to decrease oceanic oxygen (O2) concentrations, with potentially significant effects on marine ecosystems. Geologically recent episodes of abrupt climatic warming provide opportunities to assess the effects of changing oxygenation on marine communities. […] This [fossil] record … demonstrates that seafloor invertebrate communities are subject to major turnover in response to relatively minor inferred changes in oxygenation (>1.5 to <0.5 mL⋅L−1 [O2]) associated with abrupt (<100 y) warming of the eastern Pacific.
How the researchers characterize their study’s significance:
We demonstrate here that ocean sediments harbor metazoan fossil material that can be used to reconstruct the response of seafloor biodiversity to global-scale climate events. We show that the last deglaciation, the most recent episode of climate warming, was accompanied by abrupt reorganizations of continental margin seafloor ecosystems through expansions and contractions of the subsurface low-oxygen zones. This archive reveals that global climate change disturbs seafloor ecosystems on continental margins and commits them to millennia of ecological recovery.
The basic cause of the loss of biodiversity in the oceans is that warming oceans lose oxygen, which results in a die-off of invertebrate life, the foundation on which our complex ocean ecosystems are based. Once you wipe out entire species of invertebrates it can take a very long time for a complex system such as the Earth’s oceans to recover. These impacts stretch far beyond our short time-scale concerns regarding the effects of climate change on human civilization in this century.
Again from the Science News article:
This week’s study explores multicellular life–in the form of invertebrates–in pursuit of a more complete picture of ocean ecosystem resilience during past periods of climate change.
“The complexity and diversity of a community depends on how much energy is available,” says [study co-author Peter] Roopnarine. “To truly understand the health of an ecosystem and the food webs within, we have to look at the simple and small as well as the complex. In this case, marine invertebrates give us a better understanding of the health of ecosystems as a whole.”
The study’s all-important sediment core revealed an ancient history of abundant, diverse, and well-oxygenated seafloor ecosystems, followed by a period of oxygen loss and warming that seems to have triggered a rapid loss of biodiversity. The study reports that invertebrate fossils are nearly non-existent during times of lower-than-average oxygen levels.
News like this should be cause for all of us to be running around screaming with our heads on fire. It should be front page banner headline news on every media outlet, online, print or televised. Instead, it will likely be ignored or marginalized by major media outlets. And that will be not only an immensely stupid reaction, but a tragic one as well.