Hi Francisco, thanks — I’m not sure that really tells us anything! That paragraph just mentions a paper in review. In fact that website has had the same text since 2013: https://web.archive.org/web/20130313080448/http://www.environmentalstudiesinstitute.org/activities.html#climate-change

Here’s a really good, detailed discussion of what ice cores tell us, including the fact that in the past some parts of the world were very warm indeed: https://www.carbonbrief.org/factcheck-what-greenland-ice-cores-say-about-past-and-present-climate-change That fact does not conflict with what scientists say about human-caused climate change.