RRS Sir David Attenborough SD049
Cruise summary report
| Cruise Info. | |
| Ship name (ship code) | RRS Sir David Attenborough (FKAD) |
| Cruise identifier | SD049 |
| Cruise period | 2025-05-10 — 2025-05-23 |
| Status | Completed |
| Port of departure | Mare Harbour, Falkland Islands (Malvinas) |
| Port of return | Punta Arenas, Chile |
| Purpose | Research |
| Objectives | The SD049 cruise was a multidisciplinary cruise made up of 4 CASS (Collaborative Antarctic Science Scheme, CASS 223,224,226,227) projects aboard the RRS Sir David Attenborough. To fulfil their objectives the 4 projects either sampled from the uncontaminated seawater supply or installed instruments to passively air sample during passage.
CASS 223: TOMATO: Transport Of nano and Microplastics Across The Ocean. This project investigated the long-range transport of nano and microplastics across the Southern Ocean, focusing on pathways, dynamics, and environmental impacts. The project utilised airborne/atmospheric particle sampling methodologies to gather nano and microplastic samples during the late-season rotation of the Research Vessel RRS SDA. CASS 224: Winter-Air: The wintertime atmospheric ecosystem over Antarctica. This project investigated seasonal changes in the structure and function of Antarctic atmospheric microbial communities. The project collected atmospheric and underway seawater samples during the crossing of the Drake Passage and the transit down the western Antarctic Peninsula to Rothera. CASS 226: BIOPOLE-W: Biogeochemical processes and ecosystem functioning in changing polar systems during the polar Winter. This proposal aimed to collect and analyse underway seawater samples for their biogeochemical properties during a voyage along the Antarctic Peninsula between Rothera and Punta Arenas. The measurements followed BIOPOLE protocols (SD033 and SD046) to make them directly comparable to those made in other seasons. A second element of this project was to utilize the on-board echosounding facilities to determine the spatial and vertical distribution of backscattering particles (principally small pelagic organisms) to address the hypothesis that activity levels in these communities are higher than assumed during the winter period, with consequences to the sequestration of carbon to the ocean interior. A third aspect of this project was to test the ability of a small autonomous surface vehicle (ImpYak) to map the distribution and biomass of krill aggregations in inshore waters that large research vessels are typically unable to survey. CASS 227: How do marine diatoms end up in ice cores? This study aimed to better understand the processes and conditions that control the entrainment of wind-blown diatoms. To achieve this uncontaminated seawater, sea spray and surface air were sampled along a latitudinal transect during the transit to Rothera. |
| Chief scientist | Gabriele Stowasser (British Antarctic Survey), James A Bradley (Mediterranean Institute of Oceanography, Luminy) |
| Cruise report |  (2.16 MB) |
| Ocean/sea areas | |
| General | Southern Ocean Unknown |
| Specific | Drake Passage, Antarctic Peninsula |
| Track charts | (0.44 MB) |
| Measurements | |
| Physical oceanography | |
| Surface measurements underway (T,S) | Quantity: activity duration in days = 14 Description: Routine underway measurements of position, heading, speed from GPS/gyro/log; temperature, salinity, chlorophyll-a fluorescence, optical beam transmission from uncontaminated seawater supply and sensors under hull; air temperature, humidity, sea level pressure, wind speed and direction, solar radiation; |
| Transparency (eg transmissometer) | Quantity: activity duration in days = 14 Description: Routine underway measurements of position, heading, speed from GPS/gyro/log; temperature, salinity, chlorophyll-a fluorescence, optical beam transmission from uncontaminated seawater supply and sensors under hull; air temperature, humidity, sea level pressure, wind speed and direction, solar radiation; |
| Current profiler (eg ADCP) | Quantity: activity duration in days = 7 Description: Vessel-Mounted Acoustic Doppler Current Profiler measurements (VMADCP) 150 kHz (7 days). |
| Chemical oceanography | |
| Oxygen | Quantity: number of samples = 355 Description: Underway water samples for, Particulate organic carbon (POC), Particulate inorganic carbon (PIC), nutrients; Phosphate; chlorophyll-a/Lugol’s, pigments, oxygen isotopes (d18O); salinity, Particulate organic matter (POM), zooplankton, eDNA, diatoms and microbial community. |
| Phosphate | Quantity: number of samples = 355 Description: Underway water samples for, Particulate organic carbon (POC), Particulate inorganic carbon (PIC), nutrients; Phosphate; chlorophyll-a/Lugol’s, pigments, oxygen isotopes (d18O); salinity, Particulate organic matter (POM), zooplankton, eDNA, diatoms and microbial community. |
| Silicate | Quantity: number of samples = 355 Description: Underway water samples for, Particulate organic carbon (POC), Particulate inorganic carbon (PIC), nutrients; Phosphate; chlorophyll-a/Lugol’s, pigments, oxygen isotopes (d18O); salinity, Particulate organic matter (POM), zooplankton, eDNA, diatoms and microbial community. |
| Isotopes | Quantity: number of samples = 355 Description: Underway water samples for, Particulate organic carbon (POC), Particulate inorganic carbon (PIC), nutrients; Phosphate; chlorophyll-a/Lugol’s, pigments, oxygen isotopes (d18O); salinity, Particulate organic matter (POM), zooplankton, eDNA, diatoms and microbial community. |
| Other chemical oceanographic measurements | Quantity: number of samples = 355 Description: Underway water samples for, Particulate organic carbon (POC), Particulate inorganic carbon (PIC), nutrients; Phosphate; chlorophyll-a/Lugol’s, pigments, oxygen isotopes (d18O); salinity, Particulate organic matter (POM), zooplankton, eDNA, diatoms and microbial community. |
| Contamination | |
| Other contaminant measurements | Quantity: number of samples = 73 Description: Air and sea spray sampling for the microbial community, diatoms and microplastics |
| Biology and fisheries | |
| Phytoplankton pigs (eg chlorophyll, fluorescence) | Quantity: activity duration in days = 14 Description: Routine underway measurements of position, heading, speed from GPS/gyro/log; temperature, salinity, chlorophyll-a fluorescence, optical beam transmission from uncontaminated seawater supply and sensors under hull; air temperature, humidity, sea level pressure, wind speed and direction, solar radiation; |
| Phytoplankton pigs (eg chlorophyll, fluorescence) | Quantity: number of samples = 355 Description: Underway water samples for, Particulate organic carbon (POC), Particulate inorganic carbon (PIC), nutrients; Phosphate; chlorophyll-a/Lugol’s, pigments, oxygen isotopes (d18O); salinity, Particulate organic matter (POM), zooplankton, eDNA, diatoms and microbial community. |
| Particulate organic matter (inc POC, PON) | Quantity: number of samples = 355 Description: Underway water samples for, Particulate organic carbon (POC), Particulate inorganic carbon (PIC), nutrients; Phosphate; chlorophyll-a/Lugol’s, pigments, oxygen isotopes (d18O); salinity, Particulate organic matter (POM), zooplankton, eDNA, diatoms and microbial community. |
| Phytoplankton | Quantity: number of samples = 355 Description: Underway water samples for, Particulate organic carbon (POC), Particulate inorganic carbon (PIC), nutrients; Phosphate; chlorophyll-a/Lugol’s, pigments, oxygen isotopes (d18O); salinity, Particulate organic matter (POM), zooplankton, eDNA, diatoms and microbial community. |
| Phytoplankton | Quantity: number of samples = 73 Description: Air and sea spray sampling for the microbial community, diatoms and microplastics |
| Zooplankton | Quantity: number of samples = 355 Description: Underway water samples for, Particulate organic carbon (POC), Particulate inorganic carbon (PIC), nutrients; Phosphate; chlorophyll-a/Lugol’s, pigments, oxygen isotopes (d18O); salinity, Particulate organic matter (POM), zooplankton, eDNA, diatoms and microbial community. |
| Pelagic bacteria/micro-organisms | Quantity: number of samples = 355 Description: Underway water samples for, Particulate organic carbon (POC), Particulate inorganic carbon (PIC), nutrients; Phosphate; chlorophyll-a/Lugol’s, pigments, oxygen isotopes (d18O); salinity, Particulate organic matter (POM), zooplankton, eDNA, diatoms and microbial community. |
| Acoustic reflection on marine organisms. | Quantity: activity duration in days = 7 Description: Simrad EK80 bioacoustic echosounder |
| Other biological/fisheries measurement | Quantity: number of samples = 355 Description: Underway water samples for, Particulate organic carbon (POC), Particulate inorganic carbon (PIC), nutrients; Phosphate; chlorophyll-a/Lugol’s, pigments, oxygen isotopes (d18O); salinity, Particulate organic matter (POM), zooplankton, eDNA, diatoms and microbial community. |
| Other biological/fisheries measurement | Quantity: number of samples = 9 Description: Snow and glacier ice sampling for microbial community |
| Other biological/fisheries measurement | Quantity: number of samples = 73 Description: Air and sea spray sampling for the microbial community, diatoms and microplastics |
| Meteorology | |
| Routine standard measurements | Quantity: activity duration in days = 14 Description: Routine underway measurements of position, heading, speed from GPS/gyro/log; temperature, salinity, chlorophyll-a fluorescence, optical beam transmission from uncontaminated seawater supply and sensors under hull; air temperature, humidity, sea level pressure, wind speed and direction, solar radiation; |
| Geology and geophysics | |
| Single-beam echosounding | Quantity: activity duration in days = 12 Description: EA640 singlebeam echosounder recording. |
