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What a terrible article... It claims there is 'A lot' of pollution coming from China specifically and ending up in California. The way they deduced this 'fact

What a terrible article... It claims there is 'A lot' of pollution coming from China specifically and ending up in California. The way they deduced this 'fact' is that 208Pb levels spiked at the same times in both China and California. That tells you absolutely nothing.

fiatmoney 13y ago
The paper goes into greater detail; "a lot" ~ 29% in this case. Using regionally specific isotope mixes to identify sources of pollution seems like a pretty good idea; why shouldn't it work?
- seandougall 13y ago
  Well, the article makes it sound like they're basing the research on the assumption that the 208Pb comes from Asia simply because it spikes in the spring. I would hope they have reason to believe in the specificity of that marker for Asian pollution, rather than actually engaging in such wild speculation, but if they do, the article skips over it. Also, the non-sequitur about iPhones and iPads at the end is completely random and seemingly pointless. Also needs "[2010]".
  - kaybe 13y ago
    The article is wrong. From the abstract: 'We tested whether Pb isotope ratios in airborne particles can be used to directly evaluate the Asian contribution to airborne particles of anthropogenic origin in western North America, using a time series of samples from a pair of sites upwind and downwind of the San Francisco Bay Area. Our results for airborne Pb at these sites indicate a median value of 29% Asian origin, based on mixing relations between distinct regional sample groups.' If it was unfounded, the reviewers would have shot it down.
jamesaguilar 13y ago
This comment is not accurate. Both locations measured were in California. The correlation to Asia is the timing of the spikes and dust storms in Asia. Not a climate scientist, so I don't know how good of an argument that is, but if you're going to post a strongly worded response you best characterize the opposing arguments correctly.
- kaybe 13y ago
  The correlation is the ratio of the lead isotopes, which is specific for that Asien region. Lead from other sources has a different isotope ratio. (Don't have data right now so I don't know how specific it is.) (Of course, mixing has to be taken into account when backtracking.) It is actually a pretty good argument. However, it only applies to PM2.5 lead itself, since different materials can behave very differently (chemistry etc). Also, how and where the lead came from the metal ores and coal into the air is not part of the research.

fiatmoney 13y ago

The paper goes into greater detail; "a lot" ~ 29% in this case. Using regionally specific isotope mixes to identify sources of pollution seems like a pretty good idea; why shouldn't it work?

seandougall 13y ago
Well, the article makes it sound like they're basing the research on the assumption that the 208Pb comes from Asia simply because it spikes in the spring. I would hope they have reason to believe in the specificity of that marker for Asian pollution, rather than actually engaging in such wild speculation, but if they do, the article skips over it. Also, the non-sequitur about iPhones and iPads at the end is completely random and seemingly pointless. Also needs "[2010]".
- kaybe 13y ago
  The article is wrong. From the abstract: 'We tested whether Pb isotope ratios in airborne particles can be used to directly evaluate the Asian contribution to airborne particles of anthropogenic origin in western North America, using a time series of samples from a pair of sites upwind and downwind of the San Francisco Bay Area. Our results for airborne Pb at these sites indicate a median value of 29% Asian origin, based on mixing relations between distinct regional sample groups.' If it was unfounded, the reviewers would have shot it down.

jamesaguilar 13y ago

This comment is not accurate. Both locations measured were in California. The correlation to Asia is the timing of the spikes and dust storms in Asia. Not a climate scientist, so I don't know how good of an argument that is, but if you're going to post a strongly worded response you best characterize the opposing arguments correctly.

kaybe 13y ago
The correlation is the ratio of the lead isotopes, which is specific for that Asien region. Lead from other sources has a different isotope ratio. (Don't have data right now so I don't know how specific it is.) (Of course, mixing has to be taken into account when backtracking.) It is actually a pretty good argument. However, it only applies to PM2.5 lead itself, since different materials can behave very differently (chemistry etc). Also, how and where the lead came from the metal ores and coal into the air is not part of the research.