The Cliflo API from New Zealand's National Institute of Water and Atmospheric Research (NIWA) gives access to data from 6,500 climate stations maintained by the government of New Zealand. The API webpage notes that access is by subscription, though the cost is free, suggesting that only registration and agreement with the terms and conditions are required. Access to data gathered by Pacific Island stations is restricted by agreement with Pacific Island countries. However it is possible to obtain access by permission.
Our API directory now includes 195 science APIs. The newest is the AnnotQTL API. The most popular, in terms of mashups, is the NCBI Entrez API. We list 4 NCBI Entrez mashups. Below you'll find some more stats from the directory, including the entire list of science APIs.