The phrase "temperature difference" refers to the disparity or variation in temperature between two objects or locations. It is a way to describe how much colder or warmer one thing is compared to another. Full definition
Note the decreased temperature difference between equator and poles, as also observed and projected under the modern climate change. (bitsofscience.org)
And it now seems that the risks of such droughts can be read in advance in the details of temperature differences in two oceans. (climatenewsnetwork.net)
Students may not be impressed with such a small temperature difference in the laboratory. (rsc.org)