Update: This post has changed to correct a mistake I made with the ERA-5 data.
I keep hearing about such-and-such month being the “hottest such-and-such month on record.” October of this year, for example. For data sources like NASA and NOAA in the U.S. and HadCRU in the U.K., the time needed to do the computations (mainly waiting for all the observing stations to report) delayed such announcements until mid-month, but lately I’ve been hearing it early in such-and-such month, often based on announcements from the Copernicus Climate Change group in Europe. I think they base their announcments on the ERA-5 data, a re-analysis data set, which incorporates both observed data and computer simulation.
I looked at the ERA-5 data, which starts in 1979 (probably because that’s when the satellites really kick in). The interesting thing is that it doesn’t just show increase, it shows (statistically significant) acceleration.
I’ve formed a gridded composite sea level estimate and I’d like to share it. It’s quite crude, but some compensation is necessary because a simple average of stations is dominated by Europe and North America, there are so many tide gauge stations there. My regional breakdown was a first step; this is the next.
I divided the world into 30° x 30° latitude-longitude grids, and within each, aligned all the tide gauge stations with at least 360 monthly values since the year 1900. Then I aligned all 47 grid series (which actually had data), area weighted, to get a global estimate:
Mary Ellis Steven is excited about meeting Greta Thunberg this Friday, at her climate strike in Charlotte, North Carolina.
So excited to have the one and only @GretaThunberg join my strike this Friday!
See you there, Charlotte! https://t.co/lgsrFLeOs8
— Mary Ellis Stevens (@_Mary_Ellis) November 7, 2019
Mary, you are Greta Thunberg.