The island, which will be named Lynettehold, will be connected to the mainland via a ring road, tunnels, as well as a public metro line. It will measure around 1 sq mile (2.6 sq km), and the project is expected to begin later this year.

The government has said the artificial island is expected to function as a barrier against future flooding resulting from storm surges and sea-level rise — two problems that are expected to exacerbate as climate heating continues to take its toll. The island is also expected to house some 35,000 people.

“Lynetteholm will provide effective storm surge protection for Copenhagen from the north and thus provide security for the city’s citizens, who are likely to experience more extreme weather in the coming decades,” Denmark’s transport minister Benny Engelbrecht said in a statement last year.

Denmark is among the countries with some of the most ambitious climate plans, vowing to reduce its emissions by 70% (compared to 1990 levels) within 10 years. As a low-lying country (the country’s highest altitude is 173 meters above sea level), the country is also more exposed to the effects of climate change, especially when it comes to storms and sea-level rise. It is hoped that the artificial island will mitigate some of these problems for Copenhagen, especially protecting its port, which is one of the largest in Europe.

Anne Skovbro, CEO of urban developers By & Havn who will work on the island's construction, welcomed the parliament's cross-party decision.

"Lynetteholm is an important future and climate protection of Copenhagen for the benefit of the city's young and future generations," she said in a statement.

But not everyone is excited about the program. In fact, some environmentalist groups were so upset at the project they took it to court. The groups argued that the movement of sediment at sea can affect local ecosystems and the water quality. In addition, the project will require a fleet of lorries to travel through the city every day.

Frederik Roland Sandby, the Secretary-General of the Climate Movement in Denmark ("Klimabevægelsen i Danmark"), dismissed the project's environmental benefits as another example of "greenwashing". Sandby and his organization are suing the Danish government, calling the approval of the project "startling".

Among the project's downsides which Sandby names is the extra congestion, pollution, and emissions that the island's construction will require. The project construction is expected to last until 2070. It's a project that will have long-term impacts on the city of Copenhagen.

Passing the recent vote isn't the last hurdle the project will have to face. The project is also being challenged in the European Court of Justice, on the grounds that the environmental assessment only looked at the island itself, not on the effects that the other developments (housing, transportation will have).