I am completely new to Arduino but have the idea that I could manage - with some help from others - to do some (coarse) temperature monitoring with one, or even several,  -80°C freezers in a bio-laboratory.

Actually the purpose of the system is not really a precise temp. monitoring, but more of an alarming system which would alert when the temp. in one of the freezers is crossing a certain threshold (e.g. -60°C). The precision should be better than +/-5°C in the relevant temperature range [-80°C, -50°C].

The professional systems I am aware of make use of PT1000 temperature sensors, but when I googled for "Arduino PT1000" I found a number of dis-encouraging  comments of that combination - at least for my (lower) level of knowledge (extra circuits and highest precision reference voltage needed).

It would help to know if my (presumably) low level requirements could be accomplished with a more simplistic Arduino setup with some additional  resistors, caps and cables. Any chance?

PS: Later I could add an Ethernet shield (and some code) for accessing the status remotely.