Experts have long thought it was out there, but now we've got confirmation – there's a second garbage patch of plastic out in the Pacific Ocean, which may cover as much as 2.6 million square kilometres (a million square miles), or 1.5 times the size of Texas.

Like the patch of floating debris in the North Pacific, this one in the South Pacific has been formed by a swirling mix of currents and winds called a gyre, concentrating plastic waste into one area.

As depressing as the news is, it's not entirely surprising: the research team that found patch number two has been searching for it for six months, and a recent study highlighted the huge volumes of plastic washing up on Henderson Island in the same part of the ocean.

Now researchers have actually been to visit the site of the South Pacific Garbage Patch and collect samples.

"We discovered tremendous quantities of plastic," oceanographer Charles Moore from the Algalita Marine Research Foundation, told ResearchGate. "My initial impression is that our samples compared to what we were seeing in the North Pacific in 2007, so it's about ten years behind."

plastics ocean 02Collecting samples on the Algalita research vessel. Credit: Algalita Marine Research Foundation

Moore and his team sailed around Easter Island and Robinson Crusoe Island during their trip, using drag nets to collect plastic waste for analysis.

Most of the plastic the researchers found wasn't in the form of water bottles or shopping bags but rather tiny plastic pieces smaller than grains of rice – and that indicates this debris has been on a longer journey than the trash in the North Pacific.

As these bits of plastic are so tiny they're very difficult to clean up, and we really need to be stopping this stuff getting into our oceans in the first place.

The researchers will need to properly weigh and analyse their samples before officially publishing their findings, but wanted to get news of their discovery out early so we can begin to think about how to tackle the problem.

plastics ocean 03Plastic collected from the South Pacific. Credit: Algalita Marine Research Foundation

"There's very little information on plastic in the South Pacific," oceanographer Erik van Sebille, from Utrecht University in the Netherlands, told ResearchGate. Sebille wasn't involved in the expedition but is working on a project to track all of the plastic in our oceans.

"Hardly anybody goes there, and it's really very poorly studied. We need observations like these to constrain our modelling, so I was excited to see Charles' project. It'll feed nicely into that."

With plastics concentrated into smaller groups within the entire patch, it's going to need several journeys crisscrossing the area to work out the full extent of what we're looking at, but this new report is another sign of how big the problem has got.

We're putting millions of tonnes of plastic into the oceans every year, and the amount keeps on rising. While you might not think a patch of debris out at sea is much to worry about, there's concern about its impact on marine life – and anything that affects the ocean ecosystem also affects us on land.

It looks like the patch is filling up fast, too: marine pollution researcher Marcus Eriksen from the 5 Gyres Institute, who wasn't part of this trip, sailed through the area in 2011 and saw very little plastic debris.

"Gone are the silly notions that you can put nets in the ocean and solve the problem," said Eriksen. "This cloud of microplastics extends both vertically and horizontally. It's more like smog than a patch."

"We're making tremendous progress to clean up smog over our cities by stopping the source. We have to do the same for our seas."