How long have we had instruments that accurately recored global temps?

Question

I'm not talking about a simply thermometer.

Answer 1

There is no such instrument,even now. We are dependent on a large number of well calibrated and precise instruments placed at strategic locations.

We can answer more accurately the change in temperature at a thousand points than we can give an actual number of degrees mean for the earth.

Answer 2

The above answer your question but I think you may be asking the wrong question!

We may not have instruments to measure temperature for long but we do have a number of ways of accurately measuring the Earth's temperature over millions of years (e.g. ratio of gas isotopes caught in air pockets in polar ice).

There is no instrument that can "measure" my age yet it is quite possible to know very accurately how old I am - ask me, look up my birth certificate and other reasonably accurate ways (e.g. examining bones and teeth after my death)

Answer 3

There are two datasets of long-term global temperature anomalies in wide use among scientists.

NASA's Goddard Institute for Space Studies (GISS) maintains a global dataset that goes back to 1880. The GISS dataset interpolates missing data, especially near the poles. You can find it here:

http://data.giss.nasa.gov/gistemp/tabled...

The Hadley Centre, a branch of the UK's Meteorological Office, maintains a global dataset that goes back to 1850, but without interpolating missing data. The current version of this dataset is called HADCRUT3, and you can find it here:

http://hadobs.metoffice.com/hadcrut3/dat...

Answer 4

still nothing that accurate

Answer 5

Well, some would say about 30 years with infrared instruments on satelites.  They found they were in error though and their results had to be retro-adjusted a year ago.

Therefore, I would say we've only had them about a year.  Surely NOW they've got it right.

Answer 6

Sattelites that measure temperatures were deployed around thirty years ago.  One of the reason why some say they are not "accurate" is because they do not support the alarmist arguments.

Answer 7

The most advanced instruments that provide the most precise measurements have been around for less than the past decade.

Answer 8

Average global temps? It depends on what you mean by accurate--the error bars are very large even now. Even with satellites, the margin of error is huge.