I worked for many years designing microprocessors. I very likely designed parts of the microprocessor in your computer, Playstation and X-Box. In the microprocessor design business, companies hire large teams of verification engineers, whose job it is to find faults with the design. These companies can’t afford to have any bugs when their product gets to market.
Government agencies like NCDC have the opposite problem – they are pushing a global warming agenda and can’t afford to release any correct information. So they make press releases without doing any comparison vs. real data. NCDC just announced that April was the warmest on record globally. Had they done any comparison vs. much more accurate satellite data, they would have known that they were wrong.
NCDC global temperatures are diverging from satellite data at a rate as large as their claimed warming trend.

www.ncdc.noaa.gov/cag/time-series/global/globe/land_ocean/p12/12/1880-2014.csv
rss_monthly_msu_amsu_channel_tlt_anomalies_land_and_ocean_v03_3.txt
In other words, NCDC’s data and press release is complete nonsense, with no factual basis behind it. So they are doing the job the White House has tasked them with.