One interesting data point here is that recent academic research suggests air pollution in Hebei did NOT fall.
nber.org/papers/w27086
Recent @NASAdata reveals that air pollution in north India has dropped to a 20-year low. In Delhi, the levels of harmful PM 2.5, plunged after the lockdown began — falling from 91 mg per cubic metre (mg/m3) on March 20. insightful piece by @samirsaran & @jayantsinha
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We don't have the Apple/Google data on mobility in China. So we don't have a great comparison.
But at least on the air pollution data where we CAN compare, the evidence that Hubei had a tighter lockdown than eg France or Italy or Spain is pretty weak.
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Comparisons to Lunar New Year seem like a good reference, though.
May 9, 2020 · 6:55 AM UTC

