In Haltia there's also interesting temporary exhibitions:
Finnish Nature Photo of the Year 2020 (Vuoden luontokuva) winners 23.10.2020-10.1.2021
Blue for a Bee by Michael Rahikainen 23.9.2020-17.1.2021
Best of "Nature picture of the year 2016-2018"
Come to Finland -posters from the 1900s
A textile work of Forest nature diversity, made by students at Omnia. Read more in Finnish
Archive of the previous Temporary exhibitions (with information in English):