There are plenty of conferences related to environmental policy, management and technology. There is a database that stores all the information needed. https://conferenceindex.org/. It is possible to look for the conferences by Category, Tag, Country or City.
Some of the most well-known conferences about remote sensing and environment are the following:
International Conference on Environmental Remote Sensing and Modelling
International Association of Landscape Ecology
IEEE International Geoscience and Remote Sensing Symposium
Ecosystem Services Science, Policy and Practice in the face of Global Changes
I_Forum provides a platform for dialogue among geospatial minds, informing the GeoInformation Society, contributing to a more just, ethical and sustainable society. It is organized by ZGIS from the university of Salzburg.
Some of the conferences have changed the dates due to the COVID-19 crisis, so I cannot provide the dates because they might be cancelled. On the other hand, they can take place in an online format.
OpenGeoHub Summer School. This year, it will take place virtually: https://opengeohub.org/summer_school_2021
IGARSS Summer School. The registration is already closed but it this is to consider for the future. https://igarss2021.com/SummerSchoolProgram.php
European Association of Environmental and Resource Economists (EAERE). EAERE Summer School In Resource And Environmental Economics 2021. https://www.eaere.org/events/schools/eaere-and-uni-graz-european-summer-school-in-resource-and-environmental-economics-2021/
EAERE – ETH Winter School. Natural resources and development in resource-rich countries. https://www.eaere.org/events/schools/eaere-eth-winter-school-on-natural-resources-and-development-in-resource-rich-countries/
AniMove summer school. We are aware of the situation of Biodiversity worldwide. But how can we handle its study? Remote Sensing helps us to monitor the animal movement and habitat changes. To do so, AniMove offers courses and summer courses to know how to use R software in order to manipulate such datasets. https://animove.org/
The settled Nomadism-2022 – https://sites.google.com/view/one-project/event/summer-school-2022?authuser=0
International MARE Open Summer School 15-28 August 2022 “COME! Costal and Marine Sustainability Enacted” – https://mare-project.net/index.php/2022/06/08/mareschool/