@Leon Said
And to follow up on this, I emailed Gavin Schmidt, the NASA climatologist mentioned in the article, for his response to the accusations in the article.
Here is his response:
“The details of the history of the GISTEMP product are available here:
https://data.giss.nasa.gov/gistemp/history/
“including the impact of changes in methodology, input data etc.
“If you dig into what Tony Heller does there is a lot of glossing over why things might legitimately change over time, some deliberate confusion of sources (GISTEMP has not used USHCN for more than a decade), lots of conflation of local and global means, and a stubborn reluctance to ever acknowledge that all of the data and code (for GISTEMP, for the NOAA NCEI homogenization etc.) is publicly available and the result replicable by anyone. If there was any truth to his accusations it would be visible there.”
- Gavin
In summary, two things stand out:
1. Data sources have understandably grown more accurate over the years of research, hence the apparent disrepancy.
2. The data is public, and anyone can replicate and see it for themselves.
Also got a reply from Dr. James Hansen, the other scientist mentioned in the article. He wrote a paper, found
here that illustrates how data sources have increased in its accuracy over the decades, which is NOT akin to altering data, also noting in his email that:
“None of our data are original with us. Our analysis uses three data sources. Satellite measurements over the ocean, global weather stations provided via NOAA, and Antarctic data recorded at research stations. Deniers look for any minor, temporary problem and only report those problems of one sign -- they are not legitimate, careful scientists.”