Visualizing Oceanographic Data to Depict Long-term Changes in Phytoplankton

I am a plankton ecologist focused on characterizing the effects of rapid climate change on phytoplankton and zooplankton ecology and physiology. Plankton ecology requires both a mix of traditional and modern approaches. More recently, plankton imaging technology, in addition to microscopy, is being used to quantify and measure plankton.

This technology decreases the time it takes to manually count plankton by utilizing artificial intelligence to count, and classify plankton for us. This research visualizes one of the longest plankton time series in the world. These data sets are critical for providing context to understanding shifts in plankton communities and food webs in regions affected by rapid climate change.

My research has helped to visualize the mechanisms underpinning those shifts. Given the microscopic nature of plankton, it can be difficult, particularly for scientists to visualize and communicate how plankton communities are changing over time. My protocol aims to provide a clear method for visualizing shifts in plankton communities, leveraging scientific data within an artistic framework.

This protocol will hopefully encourage the other scientists to think more creatively about how they visualize, and present their data, particularly to non-science audience. There is often gap between lab result and how they are interpreted and present in society. So I hope this protocol will help bridge this gap.

My lab will continue to leverage plankton time series data sets to identify the environmental factors affecting long-term changes in plankton communities, as well as conduct physiological experiments in the lab to understand the physiologic mechanisms underpinning these community shifts in the Northeast United States and beyond. To begin, select phytoplankton microscopic images taken from the Narraganset Bay Long-Term Plankton Time Series as either JPEG, PNG, or PDF files. Place JPEG or PNG microscopic image into the Illustrator workspace.

Go to View, then click Show Transparency Grid to reveal the checkerboard background indicating transparent areas. Next, click on Window, followed by Image Trace in the dropdown menu to open the Image Trace window. Under the Image Trace options, click Preset, then Black and White Logo, followed by Mode, and Black and White.

Then under Properties, select Expand to vectorize it. Choose the direct selection tool and click on the white space. Delete it, and then click File, and Save As, and select EPS To save as a vector graphic.

To create phytoplankton patterns, first, create a new art board in a new workspace by clicking the square art board tool in the toolbar. Make three identical art boards of the same size by adjusting the size within Properties. Drag and drop the EPS files of the different phytoplankton taxa onto the art board.

Use the direct selection tool to draw a box around an individual phytoplankton. Under Properties select Embed, then Fill, and color the phytoplankton with the desired color from the color palette, which is representative of the decade. Then use the black arrow selection tool to highlight a particular phytoplankton.

Select Edit, then Copy, followed by Edit, and click on Paste. Paste each phytoplankton vector qualitatively based on the relative proportions of each taxa in the dataset for each of the three decades. Select Object, then Pattern, and Make to create a color swatch phytoplankton pattern for each of the three decades.

Begin by opening a JPEG or PNG figure of the chlorophyll a decadal biomass into the Illustrator workspace. Then, vectorize each of the three chlorophyll a seasonal cycles by removing the background and saving the image as an EPS file. Then create a new art board in a new Illustrator workspace by clicking and dragging the square art board tool in the toolbar.

Adjust the size by clicking on Properties and Transform to make three identical art boards of the same size. Drag and drop the chlorophyll a EPS files onto the three art boards. Go to Properties and Embed to add it to the new art board.

Create a new layer by selecting the sticky note icon. Next, create a rectangle within the new layer with the rectangle tool from the toolbar. Fill the rectangle with a light blue gradient using the gradient tool from the toolbar.

Use the line segment tool from the toolbar to create a box attached to the trend line. Make the line straight and aligned by holding the Shift button. Then, press the Control key and select all the components, including the lines and trend line within the layer.

Then, select Object, followed by Path and Join. Repeat creating a rectangle and fill it with a blue to red color gradient to represent warming water temperature across the three decadal panels. Create a third rectangle of equal size and fill it with the phytoplankton swatch pattern corresponding to that decade.

Place the grouped line segments within the layer of rectangles. Next, select the two smaller rectangles and the grouped line segments. Select Object, then Clipping Mask, followed by Make.

This will remove the top fill of the shape. Repeat creating a rectangle and fill it with a red to blue color gradient to represent warming water temperature across the three decadal panels. To add images of microscopic phytoplankton onto the phytoplankton patterns, select Open, and click on the image file to open it in the Illustrator.

Then create a circle with the ellipse tool from the toolbar and overlay it on top of the phytoplankton image. Hold the Shift key to select both the shape and the image. Then in the menu, click on Object, then Clipping Mask, followed by Make to fill the shape with the image.

Repeat for selected phytoplankton images, and distribute across the three decades to look like a magnifying glass zooming in on the illustrative phytoplankton. Now use the rectangle tool from the toolbar to create a text box on each of the decade art boards. Use the type tool to click and type information about each decade.

Add text at the top of each decade with the name of the decade, and add the names of the corresponding seasons at the bottom of each of the three panels. Import the saved illustrator file and select to only import the three completed decades. Select All and export as a PDF file.

Print the panels on heavyweight matte or paper and install with hanging hardware. Visualization of phytoplankton data showed a decline in phytoplankton biomass from the 1970s to 1990s to 2000 tens. All decades exhibited a bimodal peak in chlorophyll a concentration with the first peak occurring in winter, and the second occurring in summer.

Also, Thalassiosira and Skeletonema species increased from the 1970s to 1990s. Other taxa such as Eucampia oscillated in abundance, as shown by the increased presence of more Eucampia zodiacus images in the 2010s compared to the 1970s and 1990s.