It's not literally a low pass filter with a sinc function of course, that was an analogy. It's more like a gaussian smoothing. You're not going to get ringing i

It's not literally a low pass filter with a sinc function of course, that was an analogy. It's more like a gaussian smoothing. You're not going to get ringing in the temperature record... Here's the direct quote again if you missed it above: "We showed that no temperature variability is preserved in our reconstruction at cycles shorter than 300 years"