The Caribbean islands were the first to be hit by Hurricane Irma, a category five storm, killing 30 people and making many homeless before wreaking devastation in the United States and Cuba.

As it passed over the islands and the clouds cleared, Nasa noticed a rather drastic change.

Comparing with images that were taken just days before the storm, the US space agency noticed the islands had changed colour, from lush green to bare brown.

The images were taken by Nasa’s Operational Land Imager instrument aboard the Landsat 8 satellite on August 25 and then on September 10.

Nasa's image of Hurricane Irma.
The Carribbean Islands before and after Hurricane Irma (Landsat 8/Nasa)

“The most obvious change is the widespread browning of the landscape,” Nasa wrote.

“There are a number of possible reasons for this. Lush green tropical vegetation can be ripped away by a storm’s strong winds, leaving the satellite with a view of more bare ground.

Nasa's image of Hurricane Irma.
Virgin Gorda is a bit greener on the south and west of the island because it was partly shielded from winds by the hills in the centre (Landsat 8/Nasa)

“Also, salt spray whipped up by the hurricane can damage and desiccate leaves while they are still on the trees.”

Nasa also noted that some of the vegetation on the west side of Virgin Gorda remained because it was in area partially sheltered by hills in the centre of that island.

Nasa's image of Hurricane Irma.
Barbuda didn’t fare well but in contrast, Antigua appears relatively intact (Landsat 8/Nasa)

While the destruction is clearly visible on Barbuda, the agency says the green on Antigua appears relatively healthy and intact.

Explaining why the ocean colours were different, Nasa wrote: “Differences in ocean colour likely stem from differences in the ocean surface; rougher surfaces scatter more light, and appear brighter and lighter.”

This image taken by GOES-13 satellite shows Hurricane Irma heading towards the Caribbean islands on September 6.
This image was taken by GOES-13 satellite shows Hurricane Irma heading towards the Caribbean islands on September 6 (Nasa)

Meanwhile Zooniverse, an online organisation made up of citizen scientists, has been brought in to analyse images of the storm-hit areas, taken by the European Space Agency’s Sentinel-2 satellites, through The Planetary Response Network.

It says the last time the network was brought online was during the Ecuador earthquake in 2016, where citizen scientists analysed “almost 25,000 square kilometres of satellite imagery in only 12 hours”.