1. In 1903, the Hawaiian Volcano Observatory was established on April 22 by Thomas A. Jaggar, a geologist and volcanologist. The observatory was the first of its kind in the world to study volcanic and seismic activity, and played a critical role in advancing the study of volcanoes.

2. In 1970, the first Earth Day was celebrated on April 22, as a way to raise awareness about environmental issues and encourage individuals and governments to take action to protect the planet. Hawaii has been at the forefront of environmental conservation efforts, with a strong focus on protecting its unique and fragile ecosystems.

3. April 22, 1972 marked the signing of the Treaty of Bernice Pauahi Bishop, which established the Bernice Pauahi Bishop Museum in Honolulu as the designated repository for all cultural artifacts and natural history specimens collected within the Pacific Basin. The museum is now the largest museum in Hawaii and home to millions of objects and specimens.

4. In 1987, the state of Hawaii enacted the Hawaii State Coastal Zone Management Program on April 22. The program aims to protect and manage Hawaii's coastal resources, including beaches, coral reefs, and marine life, while also ensuring responsible sustainable development of coastal areas.

5. On April 22, 2015, the Hawaii State Legislature became the first in the nation to commit to 100% clean energy by 2045. Hawaii has since made significant progress towards this goal, increasing its use of renewable energy sources such as solar, wind, and geothermal power. The state is also working to implement energy-efficient building codes and transportation policies to reduce reliance on fossil fuels.