This week on Dezeen, we revealed the architecture, interiors, design and media projects and studios that made the Dezeen Awards 2021 longlists.

Dezeen Awards 2021 received more than 4,700 entries from 86 different countries, including Armenia, Eritrea, Germany, Latvia, Lebanon, Peru, France and Ireland.

This year's architecture longlist features 305 projects, while the interiors longlist has 300 projects. There are 308 projects competing in the design categories and 105 longlisted in the media categories, which are new for this year.

The media categories feature awards for architecture photography, video and visualisations plus websites for studios and brands.

In addition, 121 studios were selected for the studio longlist.

In UK architecture news, the controversy surrounding MVRDV's Marble Arch Mound continued, as the Westminster City Council deputy leader in charge of the project resigned with immediate effect due to spiralling costs. The budget for the landscaped viewpoint close to Oxford Street has risen from  £3.3 million to £6 million.

Another project causing a commotion is an office development by Make, which has been granted permission to replace the modernist French Railways House in Piccadilly.

The latest IPCC climate report was released this week, warning that limiting global warming to the crucial 1.5-degree threshold set out in the Paris Agreement is now virtually impossible. A number of UK climate pressure groups spoke to Dezeen about the report and about what architects and designers can do to help avert disaster.

Among the groups was Architects Climate Action Network, which this week also launched its Households Declare campaign demanding "urgent" action from the UK Government on household carbon emissions.

Danish architecture studio BIG and construction technology company ICON announced plans to create Mars Dune Alpha, a 3D-printed structure designed to simulate living on Mars, for NASA. The project could "lay the foundation for a new Martian vernacular," the studio said.

BIG also unveiled new photos of its spiralling double-helix Marsk Tower, which opened to the public in southern Denmark. The twisting Corten steel building is 25 metres tall and will function as a viewpoint overlooking a UNESCO world heritage landscape.

New projects announced this week include a monolithic campus for The Africa Institute in Sharjah, United Arab Emirates, by Adjaye Associates. The building will feature large courtyards between five high-rise blocks.

Chinese studio MAD also unveiled visuals for its cloud-like science museum in Haikou, China, designed to serve as a major tourist attraction for Haikou, in which visitors can explore science, technology and nature.

Popular projects this week included a timber-clad cabin in the Netherlands with a flexible interior, the world's largest museum dedicated to astronomy and a Seattle storage shed transformed into a backyard studio.

Our lookbooks this week focused on inventive broken-plan interiors and hotel bedrooms with standout designs.

This week on Dezeen is our regular roundup of the week's top news stories. Subscribe to our newsletters to be sure you don't miss anything.