She was the youngest speaker at COP21 and has also spoken at COP26, making a "passionate plea" to world leaders for increased action on addressing climate change.

[3] She learned about climate change from stories her grandfather told her, who spoke about the impacts of a rising ocean to their home islands.

[4] Leem has raised the concern that the island nation has "neither the funds nor the expertise" to adapt to the impending impacts, and cites scientist predictions that the country could be gone within 50 years or less.

[7] At age 18, Leem was invited to the COP21 summit by the Marshallese foreign minister Tony deBrum where she gave the closing statement.

In 2021, she spoke at COP26 in support of the Marshall Island's government pledge to achieve 100% renewable energy, presenting the opening statement for the World Leaders Summit.