The CANON process studies are large-scale topics related to the dynamics of microbial communities. These topics include harmful algal blooms (HABs), coastal eutrophication events due to agricultural run-off, upwelling-driven ocean acidifcation events, and large episodic open ocean blooms.
Harmful algal blooms
Observations from the M1 mooring, a glider regularly patrolling Line 67, a few Argo floats in the vicinity, satellite remote sensing of the ocean surface and model solutions all indicate that conditions that might lead to a harmful algal bloom (HAB) are developing. MBARI researchers load up the R/V Western Flyer with a fleet of autonomous platforms including long-range autonomous underwater vehicles (AUVs), few drifters and small moorings. A shore-based, semi-automated command and control system is prepared to integrate in-situ, remote sensing and model information to intelligently navigate the AUVs. The AUVs and moorings are deployed in a region where red tides are known to initiate presumably by the resuspension of resting stages from the sediments into an optimal growth environment. When the moorings (or AUVs) detect a resuspension event, the shore-based system instructs the AUVs to map the field with their in situ sensors as well as return samples so that investigators on the vessel or on shore can confirm if the material contains target species. If the results are positive a drifter can be deployed at the site and the fleet of AUVs used to track and map the environment in the patch developing around the drifter. Retrieved samples are returned to shore or the vessel for detailed analysis. The patch is tracked over several weeks until it decays, or another process of great interest develops. Data from the CANON network and sample analyses provide a foundation for refining models and observations aimed at improving HAB prediction and mitigation.
Coastal eutrophication events due to agricultural run-off:
Rain events, periods of intensive watering, and seasonal changes in patterns of fertilizer use locally indicate the possibility of large discharge of agricultural fertilizer into the bay. MBARI researchers load up the R/V Western Flyer with a fleet of autonomous platforms, and drifters, and deploy them in the areas of local river discharge. Mobile assets are commanded to follow the low salinity, high fertilizer plume and observe its evolution over time, tracking development of high algal biomass, secondary effects of the blooms on microbial communities and oxygen deficiency due to remineralization of sinking organic carbon from the blooms. Samples are retrieved to investigate changes in microbial composition in the bloom area. The results are made available to local authorities that may consider management decision regarding temporary limits on fertilizer use. CANON assets are in place, poised to detect and quantify the effects of the management decisions.
Upwelling-driven ocean acidification events
Observations from the M1 mooring indicate that the spring transition is occurring. During the spring transition (happening presently) the coastal ocean cools rapidly as the upwelling season begins. Cold, salty, low oxygen and pH, corrosive water is brought up over the shelf in an as yet unknown temporal and spatial pattern. Scientists want to know what these scales are so they can mimic them in the laboratory and understand the impact of the corrosive water on the biota. MBARI researchers load up the R/V Western Flyer with a fleet of LRAUVs. The vehicles are equipped with oxygen, pH, temperature, salinity, and biophysical sensors and are deployed in and around the upwelling plume. This smart fleet of fast AUVs (gliders are not able to do this because of the strong currents), potentially in concert with autonomous aerial platforms, works in a coordinated fashion to map the 4-D evolution of the corrosive waters in a detail never possible before. The information is telemetered to the shore-based system in near real-time for assimilation into models. The shore-based system integrates the model results with remote sensing data and feeds back information to the AUVs to aid in the mapping process. Data from the CANON network and sample analyses provide a foundation for refining models aimed at improving our knowledge regarding the extent and magnitude of these plumes. After multiple iterations CANON models are used to design the minimalist set of continuous observations needed to predict the development and movement of the corrosive plumes, and to open new opportunities for using this natural process as an experimental system for assessing impacts of ocean acidification.
Open ocean large episodic blooms
Observations from satellites, Argo floats and gliders deployed along the North Pacific subtropical front indicate eddies and other characteristic environmental information that might lead to the inception of a large bloom. These blooms have been observed regularly in this region around the same time of the year but have never been adequately characterized, for example with respect to whether they act to export particulate organic carbon (POC) to the deep sea or instead are remineralized near the surface. MBARI researchers aboard the R/V Western Flyer or other large vessels are carrying a fleet of autonomous platforms in anticipation of this very moment. Upon arrival on site the fleet of smart platforms is deployed and they use satellite remote sensing and onboard sensors to track the movement, development and subsequent decay of the bloom. The AUVs regularly return samples to scientists on board for detailed analysis. The patch is tracked over several weeks until it decays.