The main column is one of a series of plumes that rose above Matua Island (48.1 degrees north latitude and 153.2 degrees east longitude) on June 12. The plume appears to be a combination of brown ash and white steam. The vigorously rising plume gives the steam a bubble-like appearance; the surrounding atmosphere has been shoved up by the shock wave of the eruption. The smooth white cloud on top may be water condensation that resulted from rapid rising and cooling of the air mass above the ash column, and is probably a transient feature (the eruption plume is starting to punch through). The structure also indicates that little to no shearing winds were present at the time to disrupt the plume. By contrast, a cloud of denser, gray ash — most probably a pyroclastic flow — appears to be hugging the ground, descending from the volcano summit. The rising eruption plume casts a shadow to the northwest of the island (bottom center). Brown ash at a lower altitude of the atmosphere spreads out above the ground at upper right. Low-level stratus clouds approach Matua Island from the east, wrapping around the lower slopes of the volcano. Only about 1.5 kilometers of the coastline of Matua Island (upper center) can be seen beneath the clouds and ash.
Off the back of this volcano is the predictable response of how volcanoes emit so much more CO2 than humans. Straight from the How to Talk to a Global Warming Skeptic guide:
Objection: One decent-sized volcanic eruption puts more CO2 in the atmosphere than a decade of human emissions. It’s ridiculous to think reducing human CO2 emissions will have any effect.
Answer: Not only is this false, it couldn’t possibly be true given the CO2 record from any of the dozens of sampling stations around the globe. If it were true that individual volcanic eruptions dominated human emissions and were causing the rise in CO2 concentrations, then these CO2 records would be full of spikes — one for each eruption. Instead, such records show a smooth and regular trend. The fact of the matter is, the sum total of all CO2 out-gassed by active volcanoes amounts to about 1/150th of anthropogenic emissions.
If you haven’t seen the Grist series in “How to talk to a climate change“, I strongly recommend checking it out. It covers pretty much every recycled argument out there (with varying degrees of sophistication ranging from ‘silly’ to ‘specious’). Hopefully somebody can now tell Jennifer Marohasy exactly why we should be worried about ‘small’ changes’, or save Australian Senator Steve Fielding from looking too ignorant when he announces to the Government that he is ‘unconvinced about climate change‘.