Sentences with phrase «of ocean anoxia»

Does the onset of ocean anoxia at the end of many of these events suggest a possibility of cycle where the collapse of one civilization provides the seeds (fossil fuels) for the next?

But with atmospheric carbon climbing at an annual rate of 2 ppm and expected to accelerate to 3 ppm, levels could approach 900 ppm by the end of the next century, and conditions that bring about the beginnings of ocean anoxia may be in place.

They were able to show that episodes of extinction coincided with pulses of ocean anoxia, driven by changes in ocean circulation and nutrient levels.

In particular, the team wanted to see if separate episodes of extinction that happened during the long period of recovery were driven by episodes of ocean anoxia and other environmental changes.

Not exact matches

Previous studies demonstrated that the loss of dissolved oxygen in Earth's oceans, an effect called «marine anoxia,» played an important role in the mass extinction event.

By studying the variations of uranium isotopes recorded in carbonates, the team was able to infer global anoxia occurring throughout the ocean using samples from a single outcrop.

The model also shows that the presence of seafloor anoxia, as suggested by black - shale deposition in the proto - North Atlantic Ocean before the event, might be the result of the silled shape and lack of deep - water formation of this basin at the Late Cretaceous.

Overall our model - data comparison shows that OAE2 anoxia was quasi-global spreading from 5 % of the ocean volume before the event to at least 50 % during OAE2.

Some odd things are also going on with relation to large areas of spreading ocean anoxia — with the two most likely culprits being ocean warming and / or nutrient loading (global industrial fertilizer production).

Pauly told IPS that the recently documented rises in ocean acidity and anoxia levels in many parts of the ocean were not part of this study but will be part of future reports.

Hence CO2 ramped up ever faster in the atmosphere, further accelerating warming, until you have the same symptoms of a global - warming - mass - extinction like the end Triassic or even Permian (ocean acidification, jump in global temperatures, ocean anoxia, etc).

It also appears that there are decreasing rates of bottom water formation; that means that oxygen input to the deep ocean is probably decreasing... is it possible that we could be pushing the global oceans towards a state where bottom water anoxia is much more prevalent?

Extreme events of ocean oxygen depletion leading to anoxia are thought to be prime candidates for explaining some of the large extinction events in Earth history including the largest such event at the end of the Permian 250 million years ago.

For more than 25 years, ocean anoxia has been invoked a major cause of the Late Permian mass extinction event, and it is also inferred to have been a key control on the patterns and duration of biosphere recovery.

The model - data reconstructions show that the spread of anoxia that both events experienced, mainly resulted from an enhancement in ocean nutrient level (4 and 2 times for OAE 1a and OAE 2 respectively).