A New Zealand judge this week denied a Pacific islander's attempt to become the world’s first climate refugee. Yet the case may be "the first raindrop of [a] coming storm", observers think, that could have major implications for Canada.

Ioane Teitiota's legal fight to stay in New Zealand after his visa expired has been closely followed across the planet. Why? Because his lawyers argued Teitiota's low-lying home in the tiny nation of Kiribati is being swallowed by rising seas.

His claim was found "novel" but "unconvincing" by a high court judge, who argued that millions of people across the globe face similar circumstances, and accepting Teitiota's claim would require major changes to international law.

Nevertheless, Craig and Marc Kielburger, co-founders of the international charity Free The Children, believe "it's a question of when, not if, Canada sees its first environmental refugee claim."

Teitiota, they wrote recently, "is the first raindrop of the oncoming storm." The Canadian government appears to agree. A federal report acknowledged there could be up to one billion climate migrants worldwide by 2050.

"It seems certain that climate change will be the source of additional pressure on Canada's humanitarian immigration program to expand, perhaps substantially, in the coming decades," it read.

Geoff Dembicki reports on climate change for The Tyee.

Funding for this article was partially provided by the Climate Justice Project of the Canadian Centre for Policy Alternatives, with support from the Fossil Fuel Development Mitigation Fund of Tides Canada Foundation.