//
you're reading...

Human impacts

How Much Garbage is in the Great Pacific Garbage Patch?

Paper: Lavender Law, K.; Morét-Ferguson, S. E.; Goodwin, D. S.; Zettler, E. R.; DeForce, E.; Kukulka, T.; Proskuroski, G. Distribution of Surface Plastic Debris in the Eastern Pacific Ocean from an 11-Year Data Set. Environ. Sci. Technol. 2014. DOI: 10.1021/es4053076

Background

There’s been a lot of news floating around about “The Great Pacific Garbage Patch”, the region of the Pacific Ocean where all of our long-lasting plastic products accumulate (Read Zoe’s post about the South Pacific Garbage Patch here). While you may have seen photos showing large pieces of plastic trash floating in the ocean, most plastic pollution comes in the form of small plastic shards and beads.

Nurdles: small industrial plastic pellets (Source: Wikipedia)

Nurdles: small industrial plastic pellets (Source: Wikipedia)

Marine microplastics, small plastic pieces on the millimeter scale, are still a very new area of research; we are just beginning to understand how these materials behave, where they go, and how they impact marine species. Many plastics, like industrial pellets (nurdles) and microbeads from soaps, enter the ocean as small pieces. Others are broken down into small pieces as larger plastic debris becomes brittle and is broken down by the Sun, wind, and waves. Small plastic pieces accumulating in the ocean can harm birds and marine wildlife that ingest the plastic and suffer internal injuries. Researchers have also discovered that the plastic can host and transport invasive species or absorb and leach toxic compounds. You can read more about how microplastics interact with the environment here, here, and here).

While scientists are well aware that the Garbage Patch exists and is made up primarily of microplastics, several questions remain. For example: How big is the Garbage Patch? How much plastic does it contain? Is the Garbage Patch growing over time? How long do plastics remain in the Garbage Patch – do they degrade or eventually sink? Global plastic production increased 41% from 2002 – 2012 and every year we depend on plastic more and more in our daily lives. It is crucial that researchers find answers to the above questions and develop ways for us to minimize the release of plastics to our oceans.

Methods

http://youtu.be/g3dq07GXhxQ Kara Lavender Law and other scientists worked along with undergraduate students as part of the Sea Education Association (SEA) Semester Program to collect samples and analyze data from more than 2500 net tows taken on 97 research cruises from 2001 – 2012. 95 of these cruises were part of the . The 97th was the Plastics at Sea Cruise, which was aimed at sampling regions in the convergence zone expected to contain elevated concentrations of plastic debris. Samples were collected by dragging a mesh net along the sea surface, a method originally intended for sampling plankton. The “tow area”, the amount of sea surface skimmed by the net, was determined from the net’s width and the tow distance. After samples were collected, any plastic pieces visible to the naked eye were picked out, counted, and archived. For samples that contained very large amounts of plastic, a portion was counted and the data was extrapolated to find out about how much plastic was in the entire sample.

Results

 

CAM-MAY-Figure1

The authors found that 93% of plastic found in all 2500 net tows was from the “accumulation zone” outlined in the box within Figure 1. Concentrations in some locations exceeded 1,000,000 pieces/km2 (1 piece per square meter). The researchers used average plastic particle mass (0.014 g) and the concentrations they measured to estimate that there are 21,290 tons of microplastic floating in the eastern Pacific Ocean  – 10 times more than estimates for the North Atlantic gyre.

Oceanic gyres are convergence zones where debris floating in surface waters can accumulate. This study focused on the eastern part of the North Pacific Gyre.

Oceanic gyres are convergence zones where debris floating in surface waters can accumulate. This study focused on the eastern part of the North Pacific Gyre.

To understand the distribution of plastics observed in their data, the authors needed to understand how the surface ocean water circulates. The areas of highest accumulation were associated with the subtropical convergence zones, which occur in the central regions of oceanic gyres. The major gyres in the Pacific Ocean are shown in Figure 2. The North Pacific gyre is separated into an eastern and western gyre – here, researchers were sampling the eastern gyre. In convergence zones, surface currents from distant regions come together – anything buoyant floating along with the currents will accumulate in this region and presumably remain until they degrade or sink.

        The authors highlighted and discussed many difficulties that have plagued scientists studying microplastics:

(1) Lack of temporal trends:

This study and many others have not been able to measure any change in the concentrations of plastics over time even though we know plastic production is increasing. Theoretically, concentrations should be increasing over time. We don’t yet understand why temporal trends aren’t readily observable. One reason might be due to small-scale variability: the exact location of maximum accumulation changes over time due to changes in wind patterns, and concentrations of plastics can change drastically over small distances, so it is difficult to track changes in concentration over time.

(2) Poor spatial coverage:

Even though the North Pacific gyre has been intensively studied for plastic accumulation and this study used the most extensive data set to date, the authors noted that spatial coverage is still poor because the region is so vast. The full extent of the subtropical accumulation zones is still unknown.

(3) Plastics come in all sizes and shapes:

The plastics counted here don’t include very small microplastics that pass through the net or rare, larger pieces of plastic debris, so researchers don’t know what percentage of total plastic debris they are sampling. This is a problem many researchers have encountered, and requires more standardized methods of plastics sampling to be developed.

What Can I Do to Help?

All of this talk about marine pollution may have you wondering: “What can I do to help”? While the problem is vast and cleaning up mid-ocean gyres would be an inconceivably huge undertaking, there are things we can do to slow continued accumulation of marine debris.

The best place to start is reducing your own plastic use. Bringing your own grocery bags to the store or your own coffee cup to the cafe are two simple ways to get started. If you want to do more, organizing or joining a beach cleanup is another way to contribute. You can find out more about beach cleanups from the Ocean Conservancy and Save the Bay. You can even contribute to scientific research by sending nurdles you find on the beach to the International Pellet Watch!

More Posts About Marine Plastic Debris

“Waiter, there’s a whale in my soup: investigating the South Pacific garbage patch.” – Zoe Ruge

“Life in plastic, it’s fantastic – for microbes in the plastisphere.” – Cathleen Turner

“Double trouble: Marine plastic debris absorbs toxic pollutants.” – Carrie McDonough

“Increasing fiber in your diet… microplastics fiber, that is.” – Erin Markham

“One species’ trash is another species’ refuge: Investigating the biodiversity associated with floating plastic debris.” – Gordon Ober

Discussion

Trackbacks/Pingbacks

  1. […] “How Much Garbage is in the Great Pacific Garbage Patch?” – Carrie McDonough […]

Post a Comment

Instagram

  • by oceanbites 2 weeks ago
    Not all outdoor science is fieldwork. Some of the best days in the lab can be setting up experiments, especially when you get to do it outdoors. It’s an exciting mix of problem solving, precision, preparation, and teamwork. Here is
  • by oceanbites 1 month ago
    Being on a research cruise is a unique experience with the open water, 12-hour working shifts, and close quarters, but there are some familiar practices too. Here Diana is filtering seawater to gather chlorophyll for analysis, the same process on
  • by oceanbites 2 months ago
    This week for  #WriterWednesday  on  #oceanbites  we are featuring Hannah Collins  @hannahh_irene  Hannah works with marine suspension feeding bivalves and microplastics, investigating whether ingesting microplastics causes changes to the gut microbial community or gut tissues. She hopes to keep working
  • by oceanbites 3 months ago
    Leveling up - did you know that crabs have a larval phase? These are both porcelain crabs, but the one on the right is the earlier stage. It’s massive spine makes it both difficult to eat and quite conspicuous in
  • by oceanbites 3 months ago
    This week for  #WriterWednesday  on  #Oceanbites  we are featuring Cierra Braga. Cierra works ultraviolet c (UVC) to discover how this light can be used to combat biofouling, or the growth of living things, on the hulls of ships. Here, you
  • by oceanbites 3 months ago
    This week for  #WriterWednesday  at  #Oceanbites  we are featuring Elena Gadoutsis  @haysailor  These photos feature her “favorite marine research so far: From surveying tropical coral reefs, photographing dolphins and whales, and growing my own algae to expose it to different
  • by oceanbites 4 months ago
    This week for  #WriterWednesday  on Oceanbites we are featuring Eliza Oldach. According to Ellie, “I study coastal communities, and try to understand the policies and decisions and interactions and adaptations that communities use to navigate an ever-changing world. Most of
  • by oceanbites 4 months ago
    This week for  #WriterWednesday  at  #Oceanbites  we are featuring Jiwoon Park with a little photographic help from Ryan Tabata at the University of Hawaii. When asked about her research, Jiwoon wrote “Just like we need vitamins and minerals to stay
  • by oceanbites 4 months ago
    This week for  #WriterWednesday  on  #Oceanbites  we are featuring  @riley_henning  According to Riley, ”I am interested in studying small things that make a big impact in the ocean. Right now for my master's research at the University of San Diego,
  • by oceanbites 5 months ago
    This week for  #WriterWednesday  at  #Oceanbites  we are featuring Gabby Stedman. Gabby is interested in interested in understanding how many species of small-bodied animals there are in the deep-sea and where they live so we can better protect them from
  • by oceanbites 5 months ago
    This week for  #WriterWednesday  at  #Oceanbites  we are featuring Shawn Wang! Shawn is “an oceanographer that studies ocean conditions of the past. I use everything from microfossils to complex computer models to understand how climate has changed in the past
  • by oceanbites 5 months ago
    Today we are highlighting some of our awesome new authors for  #WriterWednesday  Today we have Daniel Speer! He says, “I am driven to investigate the interface of biology, chemistry, and physics, asking questions about how organisms or biological systems respond
  • by oceanbites 6 months ago
    Here at Oceanbites we love long-term datasets. So much happens in the ocean that sometimes it can be hard to tell if a trend is a part of a natural cycle or actually an anomaly, but as we gather more
  • by oceanbites 6 months ago
    Have you ever seen a lobster molt? Because lobsters have exoskeletons, every time they grow they have to climb out of their old shell, leaving them soft and vulnerable for a few days until their new shell hardens. Young, small
  • by oceanbites 7 months ago
    A lot of zooplankton are translucent, making it much easier to hide from predators. This juvenile mantis shrimp was almost impossible to spot floating in the water, but under a dissecting scope it’s features really come into view. See the
  • by oceanbites 7 months ago
    This is a clump of Dead Man’s Fingers, scientific name Codium fragile. It’s native to the Pacific Ocean and is invasive where I found it on the east coast of the US. It’s a bit velvety, and the coolest thing
  • by oceanbites 8 months ago
    You’ve probably heard of jellyfish, but have you heard of salps? These gelatinous sea creatures band together to form long chains, but they can also fall apart and will wash up onshore like tiny gemstones that squish. Have you seen
  • by oceanbites 8 months ago
    Check out what’s happening on a cool summer research cruise! On the  #neslter  summer transect cruise, we deployed a tow sled called the In Situ Icthyoplankton Imaging System. This can take pictures of gelatinous zooplankton (like jellyfish) that would be
  • by oceanbites 9 months ago
    Did you know horseshoe crabs have more than just two eyes? In these juveniles you can see another set in the middle of the shell. Check out our website to learn about some awesome horseshoe crab research.  #oceanbites   #plankton   #horseshoecrabs 
  • by oceanbites 9 months ago
    Feeling a bit flattened by the week? So are these summer flounder larvae. Fun fact: flounder larvae start out with their eyes set like normal fish, but as they grow one of their eyes migrates to meet the other and
WP2Social Auto Publish Powered By : XYZScripts.com