#SeaLevelRise #Oceans #CO2Storage
Hey there! So, let’s talk about sea level rise and its potential impact on the oceans’ capacity to store CO2. This is a really interesting and important topic, especially when considering the current and future effects of climate change. 🌊
First off, it’s important to understand that the ocean is a massive carbon sink, meaning it has the ability to absorb and store large amounts of CO2 from the atmosphere. This is crucial for regulating the Earth’s climate and reducing the amount of CO2 in the air, which ultimately helps to mitigate the effects of global warming. So, the question of how sea level rise may affect the ocean’s ability to store CO2 is definitely worth exploring.
Now, let’s address the factors that contribute to the ocean’s CO2 storage capacity. The ocean’s ability to store CO2 is primarily due to the water itself and the chemical processes that occur within it. When CO2 from the atmosphere dissolves in the ocean, it undergoes various chemical reactions to form different compounds, such as carbonic acid and bicarbonate. These processes essentially lock up the CO2 in the water, preventing it from re-entering the atmosphere as easily. 😯
In addition to the water itself, the ocean’s salt concentration and the life within it also play important roles in CO2 storage. The salinity of the water can impact the chemical equilibrium of CO2, affecting its solubility and retention in the ocean. Meanwhile, marine organisms, like phytoplankton and corals, also contribute to CO2 storage through processes like photosynthesis and calcium carbonate production. This means that changes in ocean salinity and the health of marine ecosystems can have implications for the ocean’s CO2 storage capacity. 🌊🌿
So, back to the original question: would sea level rise affect the ocean’s capacity to store CO2? Well, sea level rise itself may not directly impact the ocean’s CO2 storage ability, as it is more related to the physical expansion of the ocean due to the melting of ice caps and glaciers. However, the potential consequences of sea level rise, such as changes in ocean circulation patterns and ecosystem shifts, could indirectly affect CO2 storage. For instance, altered ocean currents could impact the distribution of nutrients and phytoplankton, which are critical for CO2 absorption through photosynthesis. Similarly, rising sea levels could lead to the loss of coastal habitats like mangroves and salt marshes, which are important carbon sinks. 🌍🌊
Now, here’s where things get really interesting. While sea level rise could bring about challenges for CO2 storage, it’s also important to consider the bigger picture. In the context of climate change, the primary concern is the overall impact on the environment and human society. So, when thinking about sea level rise and CO2 storage, we have to weigh the potential drawbacks against the potential benefits, especially when it comes to mitigating climate change. 🤔
For instance, rising sea levels could have negative effects on coastal communities and ecosystems, which is definitely a cause for concern. However, if sea level rise leads to the expansion of certain marine habitats, such as seagrass meadows or deep-sea sediments, it could actually enhance CO2 storage capacity. In fact, some research suggests that deeper waters may be more effective at storing CO2 than surface waters, so an expanded ocean could theoretically absorb more CO2. Oh, the complexities of environmental science! 🌱🌊
So, at the end of the day, would sea level rise be a good thing considering CO2 only? It’s a tough question, and the answer isn’t black and white. While sea level rise may bring some potential benefits in terms of CO2 storage, it’s essential to remember the broader implications of climate change and rising sea levels. The impacts on communities, biodiversity, and ecosystems must be carefully considered alongside the potential effects on CO2 storage. And, of course, the ultimate goal is to address the root causes of climate change and reduce CO2 emissions altogether. 🌏🌱
In conclusion, the relationship between sea level rise and the ocean’s capacity to store CO2 is multi-faceted and interconnected with various environmental processes. While sea level rise itself may not directly affect CO2 storage, the potential consequences and indirect effects are worth exploring. Environmental research and ongoing monitoring will continue to provide insights into the complex dynamics of our planet’s interconnected systems. It’s a challenging and evolving field, but understanding these relationships is essential for informed decision-making and shaping the future of our planet. Let’s keep asking questions, seeking answers, and working towards a sustainable future for all. 🌍💧
This is far from a complete answer (and hopefully someone more versed in ocean-atmosphere interactions and ocean chemistry will chime in), but it’s not simple to answer definitively because there are a few things working in potentially opposite directions.
At a simple level, some portion of CO2 (and other gases) will dissolve into water because they are soluble in water (e.g., [this chapter from a basic chemistry text](https://chem.libretexts.org/Bookshelves/Introductory_Chemistry/Introductory_Chemistry/13%3A_Solutions/13.04%3A_Solutions_of_Gases_in_Water)). The amount of gas that can dissolve in water will depend on the solubility – which will generally depend on the temperature of the water and partial pressure of the gas – and the amount of water into which the gas can dissovle. In isolation, more water mass into which CO2 can dissolve, e.g., from sea level rise, seems like it would lead to an increase in possible CO2 removal from the atmosphere, but there’s a few hangups:
1. Sea level is rising in part because of thermal expansion, i.e., the temperature of the ocean (especially at the surface) is going up. In general, the solubility of CO2 goes down as temperature goes up, so again in isolation (and *very* simply), increasing ocean temperatures would imply that the amount of CO2 the oceans can uptake would go down.
2. Changes in sea level also in part reflect additions of ocean mass, i.e., fresh water added to the ocean from melting of ice sheets and glaciers. This serves to decrease salinity, especially in areas adjacent to melting zones. Again, *very* simply and in isolation, decreasing salinity would generally be expected to increase solubility of CO2, thus decreasing salinity would imply that the amount of CO2 the oceans uptake would go up.
3. Both of the above were considering the behavior of a dissolving gas into a homogeneous body of water that is well mixed. The ocean is not homogeneous, and in detail, the differences in temperature and salinity are important in driving global circulation of water (i.e., [thermohaline circulation](https://en.wikipedia.org/wiki/Thermohaline_circulation)). Generally circulation is important for the ability of the ocean to uptake CO2 because in an end member of a completely stratified body of water (and ignoring biological agents for the moment), the surface would become saturated in CO2 and shut off uptake, so sinking of surface water and mixing with deeper water is critical to allowing CO2 to be distributed in more of the ocean (and thus increasing the amount of CO2 en masse the ocean can uptake as opposed to if it was limited to the surface). However, the changes in temperature and salinity described above have the potential to change details of the thermohaline circulation, which could in turn change how well dissolved CO2 at the surface is able to mix with the rest of the ocean.
4. There are *a lot* of geochemical cycles happening in the ocean that can influence CO2 solubility beyond just simple temperature and salinity changes. A big one is the amount of [dissolved inorganic carbon](https://en.wikipedia.org/wiki/Dissolved_inorganic_carbon) that is largely biologically mediated. There have been a variety of studies showing that in some places, changes in DIC have been driving decreases in the ability for the ocean (in those locations) to take up CO2 (e.g., [Thomas et al., 2007](https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2006GB002825), [Clargo et al., 2015](https://www.sciencedirect.com/science/article/pii/S0304420315300360)). These changes are not directly tied to sea level rise, but they reflect changes from the same root cause (i.e., anthropogenic climate change).
5. Sort of similar to above, it’s not just straight dissolution of CO2 in water from the atmosphere at play, but also that huge amounts of primary producers at the surface remove CO2 from the water as they perform photosynthesis (which increases the capacity for surface waters to take up atmospheric CO2) and when they die and sink, this is an important way for carbon to be transferred to and stored in the deep ocean. There are indications that increasing oceanic temperatures may be decreasing the efficiency of this process (e.g., [Cael et al., 2017](https://aslopubs.onlinelibrary.wiley.com/doi/full/10.1002/lol2.10042)).
So, how does all of this balance out? ¯_(ツ)_/¯ In all seriousness, it’s a challenging problem and I’m not aware at least of a definitive answer (but again, this outside my area of expertise, so I’ll defer to anyone with a more nuanced understanding or knowledge of the literature). It’s worth noting as well that we are still working out just how much CO2 the oceans take up in the first place (e.g., [Watson et al., 2020](https://www.nature.com/articles/s41467-020-18203-3)), which hinders our ability to know exactly which one of these effects may dominate as we move forward.
There’s a big programme of research going on into this right now in the UK, actually!
A lot of it depends how life in the ocean like plankton will respond to climate change, and getting to grips with it could significantly improve our climate projections
Short video about the programme: https://youtu.be/nWSW_yuxOv0?si=-kKzYp14VbkoyLMJ