Rachael goes to BATS

In October 2017 while on placement at Bermuda’s Institute for Ocean Science (BIOS) PhD student Rachael Shuttleworth had the amazing opportunity to take part in one of the monthly Bermuda Atlantic Time Series (BATS) cruises on board R/V Atlantic Explorer. The BATS cruises have taken place pretty much every month since they began in 1988, where they take monthly measurements of hydrographic and biogeochemical parameters through the water column at sites within the Sargasso Sea. This time series is an invaluable climate dataset which helps us tackle big-picture questions and better understand global climate change and the oceans’ response to this.

Rachael tells us about it:

When at sea the scientists and crew work shifts around the clock and it is impossible to keep up with all the different projects that are going on! The first job was to locate and recover lost glider “Jack” who had lost a wing, and suffered a shark attack!

 Searching from the bridge for glider Jack

Searching from the bridge for glider Jack

 Leaving BIOS

Leaving BIOS

Once Jack was safely on board we set off for the BATS sample site where the sediment traps were deployed. We waved goodbye to these for the week and began on the first (of many) CTD casts. The BATS team collect samples from the CTD’s for a wide range of analyses including nutrient levels, alkalinity, oxygen content, salinity, (the list goes on…!). I however was collecting samples to characterise the carbon and oxygen isotopic composition (d13C and d18O) of the water column. The water sampling came to be my favourite job on the cruise as all the scientists get together and it’s a great time to catch up with everyone!

 CTD as it enters the water and begins its’ descent to 5500m!

CTD as it enters the water and begins its’ descent to 5500m!

 Deploying a zooplankton tow

Deploying a zooplankton tow

While the weather was still calm we were able to do a couple of zooplankton tows, however the winds soon picked up and conditions got so rough that all science was called off for the next day at least. I was secretly grateful for this, since I’d had little sleep over the previous 2 days, however my stomach was less grateful…

 Sediment traps

Sediment traps

Things had calmed down by Wednesday evening and we were able to get back to work (which consisted of many, many more CTD casts, plankton tows, radiance measurements, and collection of the sediment traps). We returned back to BIOS late Friday evening with boxes upon boxes of samples to be run – writing this a week later I don’t feel I’ve even began to scratch the surface of mine…