WEBVTT FILE

1
00:00:00.040 --> 00:00:04.120
When we were coming in, we saw really substantial plumes of

2
00:00:04.120 --> 00:00:08.210
SO2 that the CalTech guys were measuring and we

3
00:00:08.210 --> 00:00:12.320
see signs of it in our instrument and then very sustained levels of the fine

4
00:00:12.320 --> 00:00:16.420
sulfate aerosol and this is something that they call "vog," which is sort of

5
00:00:16.420 --> 00:00:20.490
like fog, except it's from a volcano and

6
00:00:20.490 --> 00:00:24.570
the volcano is emitting a lot of SO2.

7
00:00:24.570 --> 00:00:28.650
Some volcanoes emit low levels all the time. I think Kilauea's emitting

8
00:00:28.650 --> 00:00:32.880
fairly high levels fairly often. This stuff oxidizes to make sulfuric acid and that

9
00:00:32.880 --> 00:00:37.020
then forms small droplets of sulfuric acid

10
00:00:37.020 --> 00:00:41.020
and when these guys take up water, they swell and make the real visible

11
00:00:41.020 --> 00:00:45.090
haze, the strong haze that we saw the whole time we were in Kona.

12
00:00:45.090 --> 00:00:49.500
Sulfuric acid is not good for you; this is a big part of acid rain

13
00:00:49.500 --> 00:00:53.590
and the same sort of chemistry happened in the U.S.

14
00:00:53.590 --> 00:00:57.690
that precipitated the Clean Air Act.

15
00:00:57.690 --> 00:01:01.730
So all the SO2 in that case was mostly from coal-burning,

16
00:01:01.730 --> 00:01:05.750
but we did a lot to clean that up and reduce acid rain,

17
00:01:05.750 --> 00:01:14.374
certainly an environmental crisis in the eastern U.S. probably 30 years ago.