Singapore has gardens on bus roofs.

In Singapore, buses have been given the green light to find new ways to reduce emissions and improve the air quality of their services.

Last month, GWS Living Art, a company specialized in urban green structures installed green roofs on 10 public buses.

While a bus might not seem like the typical location for a green roof, the installation could provide environmental and economic benefits.

According to research by Michigan State University, green roofs are great at cooling buildings, reducing flood risk, slashing polluting emissions and providing spaces for nature to thrive.

As the earth’s temperature warms, species decline and humanity migrate to cities, urban planners are trying to find innovative solutions to bring biodiversity back into the most heavily populated of environments.

The “Garden on the Move” bus campaign is part of a three-month study to test whether greenery can help lower the temperature inside the buses and reduce the amount of fuel needed to power the air-conditioning.

“While the impact of greenery on buildings has been well documented, much less is known about the effects of greenery on moving vehicles,” said Tan Chun Liang, a research fellow at the National University of Singapore who advises the initiative.

Liang hopes the research will demonstrate how cities can use plants to combat global warming and the Urban Heat Island (UHI) effect — when a city experiences much warmer temperatures than nearby rural areas, due to the heat generated and absorbed by industry, traffic, and building materials.

The bus campaign joins other green initiatives in Singapore such as the Green Mark Scheme which aims for 80% of buildings to be green by 2030 and Gardens by the Bay, an eco-friendly garden featuring solar-powered “supertrees”‘ and over 1.5 million plants.

Singapore aims to be a “Garden City,” using green spaces to connect communities, enrich biodiversity and improve the climate.

According to Meteorological Service Singapore (MSS), “Singapore’s top 10 warmest years have all occurred in the past 25 years, and eight of them were recorded in this century.”

Research from the University of Wisconsin has shown that plants can cool cities through the water that evaporates from their leaves and by shading surfaces that would otherwise absorb heat.

GWS Living Art has also installed a green roof on the top of a bus stop in Kuala Lumpur, Malaysia.

“This initiative leverages on the same overarching idea as Garden on the Move…To replace lost greenery due to urban development and to green up under-utilized pockets of urban space,” said Zhi Kin, of GWS Living Art.

If rolled out on bus stops across the city, the company hopes that rooftop plants could help reduce the temperature, purify the air around the bus stop and curb the risk of flash floods by absorbing stormwater. They also hope the initiative will reverse the decline of key species like bees, butterflies, and birds.

Malaysia is home to some of the richest biodiversity in the world. According to the Ministry of Natural Resources and Environment in Malaysia, the country has 785 known species of birds, 307 species of mammals and 2,068 species of freshwater and marine fishes.