Deepening our understanding of ocean biochemistry and ecosystems relies on observing not only the ocean surface and soil but also its boundaries with the ground levels. For years, scientists have relied on ships for mapping and observation, but today’s satellite platforms offer a way more effective and affordable solution for ocean biogeochemistry monitoring. Read on to find out how to study ocean biogeochemistry via satellites and why this monitoring is important.
What Do Ocean Biogeochemical Sensors Measure?
So, how to use a satellite platform for ocean monitoring? Modern satellite platforms allow several means of monitoring water covers from space. Some of the satellite technologies listed below are already commercialized, while others are still in the R&D phase. Still, considering how quietly satellite platforms are evolving today, we may soon see each satellite platform system on this list in commercial use.
Dissolved Oxygen
Dissolved oxygen is crucial in ocean biogeochemistry studies, and today’s satellite platforms use two sensing methods to measure its levels. The first one is electrochemical detection, and the second one — measuring oxygen luminescence. With today’s satellite platforms, measuring luminescence is simpler from the technological perspective, even though this method is less accurate than using electrochemical detection. Several cost-effective remote satellite sensors are already in testing today, allowing for a small degree (no more than 2%) of inaccuracy, even in dynamic conditions of changing tides.
Carbon Dioxide System
Monitoring carbon dioxide levels in sea waters is crucial for understanding its ecosystems and PH levels. Recently, several important advances in satellite remote sensing platforms have been made for improving PH water measurements. One way is relying on spectrophotometric sensors. This method ensures a high degree of accuracy already, even though it remains pricey, with a single commercial sensor worth $10k per unit. A more cost-effective satellite sensor can measure water surface, relying on the same principles. The logic is to measure the equilibrium between the water sample and infrared spectroscopy to calculate the medium. While the level of inaccuracy is higher, the cost is more affordable for research institutions using satellite platforms.
Ocean Nutrients
Sea nutrients, including ammonium, nitrate, silicate, as well as several trace metals, have been very hard to measure until recently, even though these indicators give the most detailed picture of biogeochemistry ocean microbes and general ecosystems. Today’s platforms can analyze bulk parameters via spectrophotometry and fluorescence. Minor changes in watercolor give observation platforms accurate data on the nutrient structure without using any reagents, which in turn, decreases reach costs. So far, the only challenge affecting measurement accuracy is the high content of salt in water, but steps are already considered to improve platform observation quality even further.
Organic Carbon Levels
Satellite platforms today employ backscattering techniques to study ocean biogeochemistry models and measure organic carbon levels. There are two ways to measure suspended particles and organic carbon levels — with acoustic and optical backscatters. Since acoustic sensors do not rely on optical signals, they ensure a greater degree of accuracy. However, optical sensors cannot be completely discarded either because they are more sensitive to smaller particles that acoustic tools cannot discern. The combination of these techniques is useful in studying the ocean floor and its ecosystems, giving a detailed picture of water biochemistry.
Fluorescence and Chlorophyll
One of the oldest is still most effective methods of studying the ocean is measuring the chlorophyll and fluorescence emitted by its phytoplankton — something today’s satellite platforms can easily manage. Measuring ocean fluorescence and chlorophyll is still one of the most reliable and cost-effective methods of monitoring the ocean with satellite platforms because the images are available in a high spectrum range most optical images can easily provide. And even though all obtained data has to go through robust series of checks before it can be considered viable, measuring fluorescence is still the primary technique of routine ocean observation.
Underwater Bio-Acoustics
Acoustic sensing gives very good insight into fish distribution and marine species availability, making it one of the primary tools of oceanic studies. In the case of satellite platforms, measuring acoustics is still somewhat tricky, but today’s platforms can capture images of marine species’ movements and habitat characteristics. Besides, the development of new acoustic cameras and platforms has been evolving rapidly in the past decade, and it’s more than likely that new satellite platforms will obtain data on underwater bio-acoustics, too.
Monitoring ocean biogeochemistry is a vital part of analyzing climate change and keeping track of the changes our home planet is going through. Satellite platforms and EOS initiatives have already helped preserve several rare animal species, not to mention gain valuable insight about our planet. And, while the ocean remains a relatively unknown element to us even now, new advances in satellite platform technology will probably change this in the near future.
