Real Dictionary

microclimate in American English
the climate of a small, distinct area, as a forest, or of a confined space, as a building
noun: the climate of a small area, as of confined spaces such as caves or houses (cryptoclimate), of plant communities, wooded areas, etc (phytoclimate), or of urban communities, which may be different from that in the general region

microclimate in British English
noun: the atmospheric conditions affecting an individual or a small group of organisms, esp when they differ from the climate of the rest of the community