[mistermann]

From the first link:

"Note how a huge swathe of South America has been labelled as “record warmest”. And what is this based on? In fact, there is virtually no temperature data available at all for that particular area, including nearly all of Brazil. The so-called record temperatures in Brazil and neighbouring countries are pure fabrication."

That seems like a pretty bold charge, how does someone who knows nothing about this tell who's telling the truth? Anyone care to weigh in?

EDIT: Seems you're downvoted to grey already, hopefully someone can still add some commentary.

[Rebelgecko]

I recently read a very convincing (to me at least) debunking of that first link, but unfortunately I'm not able to find it right now. But from memory:

The claim is that the temperature data in the first map is made up because some of its data isn't present in the second map (just look at Africa, South America, and the oceans). HOWEVER:

The first map shows a combination of two data sets. The second map only shows one of the data sets used in the first map. Not surprisingly, this means that the second map has less data.

The two graphs are also covering different time periods. The second graph covers a smaller time period, so presumably that lets them be more specific about where the temperatures are recorded. The ERSST data in the first graph goes back more than 100 years, so they don't have quite the same precision and consistency in terms of where the measurements came from. The bigger grid squares in the first map reflect that some of the data is interpolated as weather stations moved from city to city, new weather stations start coming into play halfway through the dataset, etc.

EDIT: Apparently the debunking I read was on Stackoverflow of all places. I must've fallen down that rabbit hole while looking up something totally unrelated. Here's the link: http://skeptics.stackexchange.com/questions/37119/did-noaa-p...

[cool_look]

From the stackoverflow comments its clear that theoretical models have been proposed to infer the temperature on land from the ocean database.

the main concern is that the models are pure junk science.

so saying "our models say it is so" is precisely the problem

[Rebelgecko]

Are there any specific concerns with the methodology? I didn't see any mention of that in the first link.

[cool_look]

that was just one of many many charges of tampering[1].

honestly this cristicism of the NOAA, NASA is pretty unwelcome by most HN people, so im not proposing everyone accept this immediately.

but the facts are out there and slowly if what i am saying is correct ( time will tell ) the the tampering will start being rolled back.

[1] http://www.telegraph.co.uk/comment/11367272/Climategate-the-...

[jsprunck]

Here is an analysis from a data-driven organization dedicated to listing, understanding and reducing biases in science records. They have covered the National Climate Data Center data (which apparently GISS uses).

http://berkeleyearth.org/understanding-adjustments-temperatu...

Edit: this discussion does focus on the U.S. network, where some of the articles you listed referred to data from Africa and South America, but assumedly the corrective techniques are similar.