earth's acid test听力作业

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Earth’s acid test 听力作业
邓国通
2018210210
My name is Francisco Chavez, and we’re here in Peru, studying the impacts of air sea
exchange of CO2 on processes like ocean acidification. I’ve really been studying the ocean
off Peru for over thirty-five years. Humans have introduced an awful lot of carbon dioxide
into the atmosphere. Anybody who takes a plane or rides a car is putting CO2 into the
atmosphere. Not all the CO2 actually stays there. A lot of it goes into the ocean. For
example, about a million tons of CO2 will enter the ocean in one hour today. As CO2 enters
the ocean, it combines with seawater and carbonic acid is produced. The main concerns
are that some of the organisms that live in the ocean will be negatively affected, and
affected in pretty dramatic ways. The whole ocean food chain could be affected at some
point. This is a Niskin bottle, and we’re going to send it down to collect some water so we
can make some measurements of CO2. We’re at the Institudo del Mar del Peru, IMARPE.
Now we’re going to analyze the seawater for the total amount of CO2 that’s in there. So the
syringe is essentially sucking a very precise amount of seawater into this system. We’re
adding some acid to it, so that all the CO2 becomes gas. We’re then measuring the CO2,
and this is the record that we’re collected just very recently. The blue line shows us the
CO2 in the ocean. Here in Peru, the CO2 levels are just very, very high. And so we’re
actually seeing that here from the sample we collected. Part of that reason is because of
upwelling of CO2-rich water. And when that water comes to the surface it has very high
CO2. So studying what’s happening here is a kind of window into what other places might
look like twenty or thirty years from now. We want to understand what impacts it might
have on us. The CO2 problem is big, and scientists from all parts of the world have to
collaborate on understanding that. Richard Feely from the NOAA Pacific Marine
Environmental Laboratory, he has been looking at how, as we pump CO2 into the ocean,
that water’s going to get less saturated in calcium carbonate. Coral reefs would be the first
ones to feel this effect, since they have structures that are made of calcium carbonate. And
as the ocean acidifies, those structures would dissolve. There’s a number of other small
little animals that have the same material in their shells and they would be similarly affected.
We really don’t know how CO2 is going to affect fisheries. IMAEPE is the fisheries institute;
they are responsible for keeping track of all of the stocks of fish that live in Peruvian waters.
It may be that it won’t change things at all, or it may be catastrophic. The CO2 problem is
not a local problem, it’s a global problem. And I think we’re entering a new era where
scientists no longer can afford to just be curious about the world, but they also have to
provide some insights. It seems like, you know, we can roll the dice and say well maybe
nothing will happen in the future, but nature has a way of putting us back in our place.
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