Weather changes

Climate change poses a significant global threat to the health of our oceans, compounding the ongoing anthropogenic impacts resulting from human activities.

The oceans serve as the largest sink for heat absorption on Earth. They take in 90% of the surplus heat generated by climate change. Additionally, they act as a highly effective carbon sink, taking in approximately 23% of CO2 emissions generated by human activities.

The oceans are experiencing increased acidity due to their absorption of more CO2 from the atmosphere, and simultaneously, oxygen levels are diminishing.

Climate change is leading to significant transformations in oceans, such as rising temperatures, sea level elevation, and acidification. We will talk about it in the next section.

Greenhouse gas emissions

The phenomenon of climate change stems from the buildup of anthropogenic carbon dioxide (CO2), methane (CH4) and other greenhouse gasses in the Earth's atmosphere.

The pace at which this accumulation occurs is contingent upon the volume of CO2 emissions generated by human activities and the extent to which this surplus CO2 is assimilated by plants and soil or transported downward into the ocean depths by plankton.

According to Woods Hole Oceanographic Institution, it indicates that the oceans currently absorb approximately 50 times more of the CO2 generated through the combustion of fossil fuels.

Without this absorption capacity, the levels of atmospheric CO2 would be notably higher than the present concentration of 355 parts per million by volume (ppmv) - potentially ranging around 500-600 ppmv.

Heat absorption

Temperature plays a crucial role in the dissolution of carbon dioxide.

Colder water is more effective in dissolving and absorbing gasses such as CO2 when compared to warmer water. This is why a significant portion of carbon dioxide is dissolved in the coldest waters of the ocean.

Due to its high heat capacity, the ocean possesses the ability to absorb a considerable quantity of heat without experiencing a significant rise in temperature.

As the atmosphere becomes warmer due to the emissions of greenhouse gasses, the ocean serves as a reservoir for heat, absorbing a substantial proportion of the surplus heat.

However, with the ongoing warming of the ocean, similar to the global trend, the efficiency of the ocean in absorbing carbon dioxide is expected to decrease. In fact, there is a possibility that the ocean might start releasing carbon dioxide back into the atmosphere at a faster rate.

Solar radiation

Solar radiation is the term used to describe the energy emitted by the Sun. This energy is then absorbed by the Earth and transformed into thermal energy, commonly known as heat.

As solar radiation passes through Earth's atmosphere, a portion of the energy is reflected, while the remaining portion is absorbed. The Earth's surface and oceans are primarily warmed by solar radiation emitted by the sun.

While natural fluctuations in solar radiation can impact ocean temperatures over extended periods, the present trajectory of ocean warming is primarily attributed to human-driven factors.

Feedback loops

The process of ocean warming can set off additional warming through feedback loops. As an instance, when warmer waters cause sea ice to melt, the Earth's surface loses its reflective quality (lower albedo), causing it to absorb a greater amount of sunlight and heat.

This phenomenon creates a cyclical pattern of intensified warming, contributing to the ongoing increase in temperatures.

Climate changes

Increasing ocean temperatures are making extreme weather events more intense. This is because warmer oceans can lead to stronger storms and disturb global weather patterns.

Warmer surface waters serve as a source of energy for hurricanes and other tropical cyclones, intensifying their occurrence and impact. The record-breaking 2020 Atlantic hurricane season, generating 30 named storms, could offer a glimpse into upcoming hurricane patterns.

Rising ocean temperatures are changing weather patterns because of the ocean's role in global water circulation. The ocean's vastness affects processes like evaporation and precipitation that drive weather.

Warmer sea surfaces lead to more evaporation, adding moisture to the air above the oceans. This extra water vapor intensifies rainfall and snowfall during storms, impacting both coastal and inland areas.

Areas with lots of rain will likely get even more, while dry regions could become even drier due to shifts in the water cycle caused by ocean warming.

Melting of icebergs and glaciers

As the atmosphere and oceans undergo warming, the melting of ice sheets and mountain glaciers is taking place, leading to the infusion of freshwater into the ocean.

Since the early 1900s, a significant number of glaciers worldwide have undergone rapid melting. This phenomenon can be attributed to human activities, particularly the emission of carbon dioxide and other greenhouse gasses since the industrial revolution.

These emissions have led to elevated temperatures of the ocean, especially pronounced in polar regions, causing glaciers to melt rapidly, break off into the sea, and withdraw from their land-based positions.

The melting of glaciers contributes to the rise in sea levels, consequently amplifying coastal erosion and elevating the impact of storm surges.

This occurs as the warming air and ocean temperatures interact with the increased volume of water from melting glaciers, exacerbating the effects of these natural processes.

As the Arctic experiences the melting of sea ice, its native wildlife, such as walruses, face habitat loss, while polar bears are forced to spend more time on land.

This shift has led to an increase in conflicts between human populations and polar bears due to their increased proximity.

Rise of sea level

The escalation of sea-level rise has gained momentum in recent years due to amplified ice loss in the polar regions of the world.

The most recent data provided by the World Meteorological Organization underscores that the global average sea level reached an unprecedented peak in 2021, with an average annual increase of 4.5 millimeters observed between 2013 and 2021.

Driven by ocean warming, these dangers are reshaping vital ocean ecosystems, affecting everything from primary productivity to species distribution. The consequences for fisheries and aquaculture pose a risk to food security for millions and the global economies reliant on them.

1. Ocean acidification

Ocean acidification and global warming, while distinct issues, are intricately connected due to their shared underlying cause: human emissions of carbon dioxide.

The current atmospheric levels of carbon dioxide surpass those of the past 800,000 years, and potentially even exceed levels from the last 20 million years, forging a strong linkage between these two critical challenges.

About one-third of the carbon dioxide released into the air by human activities is taken in by the ocean. This helps mitigate some climate effects. However, when carbon dioxide dissolves in seawater, it creates carbonic acid, which lowers the water's pH value.

According to WHOI, currently approximately 50% of the human-generated (anthropogenic) carbon dioxide in the ocean is located within the upper 400 meters (1,200 feet) of the water column. The remaining 50% has infiltrated into the lower thermocline and the deep ocean layers.

This significant alteration in ocean chemistry poses challenges for calcifying organisms like corals, shellfish, and certain plankton species, which serve as the foundation of the marine food chain.

Their ability to grow, reproduce, and construct protective shells and skeletons is compromised by this profound change.

At present, the ocean's pH level is approximately 8.1, indicating a 25 percent surge in acidity. With the continuous increase in atmospheric carbon dioxide levels, seawater acidity could potentially decrease to 7.8 by the year 2100.

The ongoing process of ocean acidification poses a direct threat to crucial marine ecosystems and the livelihoods of individuals dependent on fishing and aquaculture for sustenance and economic stability.

2. Coral bleaching

Coral reefs are essential ecosystems that harbor an incredible array of marine life, hosting a remarkable 25 percent of the total fish population in the oceans. Beyond their ecological significance, these reefs play a pivotal role in bolstering local economies.

They provide crucial support to fisheries, act as natural barriers against destructive storm surges and flooding, and attract tourists seeking their beauty and biodiversity.

However, corals are HIGHLY sensitive to even slight shifts in ocean temperature. Remarkably, even a modest rise in temperature by 2–3°F can significantly alter the composition of a reef.

The heightened temperature puts stress on the corals, prompting them to expel the algae and consequently lose their color—a phenomenon termed coral bleaching.

During a bleaching event, corals lose their vibrant color but remain alive. The main reason behind this phenomenon is the departure of their symbiotic algae called zooxanthellae, which also serve as their primary food source.

While corals can catch small food particles using their tentacles, they typically rely on the nutrients provided by zooxanthellae.

In certain instances, zooxanthellae may return to the corals, leading to their recovery and growth. When the water temperature returns to normal within a span of a few weeks, corals have the potential to recover from a bleaching event.

Unfortunately, more often than not, prolonged bleaching leads to the starvation and eventual demise of corals.

3. Marine heatwaves

(Source: NOAA - Marine Heatwave Area Percentage Monthly Forecast)

The impact of climate change extends beyond just land-based heatwaves; it also induces perilous heat waves within the ocean, known as marine heatwaves. These extended periods of elevated ocean temperatures, surpassing the norm, can have far-reaching consequences.

Climate change is responsible for inducing perilous heatwaves both on land and within the oceans. Specifically, marine heatwaves constitute extended periods characterized by ocean temperatures exceeding their usual norms.

These anomalies in ocean temperature can have severe consequences, including the emergence of harmful algal blooms, instances of coral bleaching, and catastrophic mass die-offs among marine life such as fish and seabirds.

The ramifications of marine heatwaves extend far beyond the immediate heat stress, often leading to significant ecological imbalances and disruptions.

A noteworthy example of the impact of marine heatwaves is their detrimental effect on commercial fisheries in the Pacific Ocean. These events compel fish populations to migrate towards cooler waters, leaving the traditional fishing grounds decimated.

Moreover, the renowned Great Barrier Reef has faced the dire consequences of marine heatwaves, resulting in extensive coral bleaching events that have left this iconic ecosystem significantly compromised.

Marine heatwaves are a relatively new research focus. While they aren't entirely novel, scientists believe their characteristics – frequency, strength, and duration – are shifting due to ocean warming.

As the ocean absorbs more atmospheric heat, marine heatwaves might become more prevalent in the 21st century.

Economic loss

'The Anticipated Effects of Climate Change on the Ocean Economy' report comprehensively evaluates the potential consequences of ocean warming on the oceanic economy.

This study delves into the global and local repercussions of climate change on three major contributors to ocean-driven economic activities and employment: marine and coastal tourism, wild capture fisheries, and marine aquaculture.

With a keen focus on these significant pillars of the ocean economy, the report systematically examines how climate impacts might reverberate across these sectors.

By analyzing the intricate dynamics between climate change and the oceanic economy, the report aims to offer a comprehensive understanding of the potential shifts in these sectors.

According to the latest report from the Intergovernmental Panel on Climate Change (IPCC), the consequences of climate-induced deterioration in ocean health are projected to have substantial economic repercussions.

By 2050, these impacts are estimated to lead to a global economic cost of approximately $428 billion annually, and this figure is expected to escalate significantly to $1.98 trillion per year by the year 2100.

This report underscores the magnitude of the financial implications associated with the decline in ocean health due to climate change.

It serves as a stark reminder that the effects of environmental degradation have far-reaching consequences not only for the planet's ecosystems but also for the global economy.

As the world grapples with the challenges posed by climate change, this estimate provides a critical insight into the urgency of implementing proactive measures to mitigate the damage and foster a more sustainable and resilient future.

Every second breath of oxygen that we take originates from oxygen generated by marine life.

- Mr. Peter Thomson, UN Special Envoy for the Ocean

1. Reduce greenhouse gas emissions (GHGs)

Greenhouse gasses constitute the primary contributors to air pollution, encompassing compounds like carbon dioxide, methane, nitrous oxide, and sulfur hexafluoride.

While certain gasses result from natural occurrences, such as respiration by animals and plants, the amplification in their concentrations is largely attributed to human endeavors like the combustion of fossil fuels, the cultivation of livestock, and the discharge of emissions from vehicles.

A crucial measure involves decreasing the level of carbon dioxide in the atmosphere. As outlined in the Paris Agreement, the aim is to cut down carbon emissions by approximately 1 to 2 million tons annually.

As per the Arbor Day Foundation, a mature tree has the remarkable capacity to absorb over 48 pounds of carbon dioxide from the atmosphere in just one year. In this ecological exchange, the tree releases oxygen, benefiting the environment and contributing to a healthier ecosystem.

Mitigating pollution involves the reduction of human-caused emissions of harmful substances.

Pollution can worsen conditions like hypoxia and ocean warming, particularly in coastal areas, while also heightening the vulnerability of marine organisms and ecosystems to factors associated with climate change.

By adopting renewable energy sources, implementing energy-efficient measures, and embracing environmentally conscious practices, the industry can play a significant role in promoting the sustainable utilization of resources, safeguarding ecosystems, and fostering social and economic prosperity.

2. Ocean Alkalinization

Alkalinity refers to the capacity of a solution to neutralize acids. By elevating the alkalinity of the upper ocean, the capacity of seawater to store carbon can be augmented, leading to an increased ability to absorb more CO2 from the atmosphere.

Ocean alkalinization strategies encompass introducing minerals or alkaline solutions containing carbonates into the ocean. These substances interact with carbon dioxide (CO2) and water, resulting in the formation of bicarbonate (HCO3–) and carbonate (CO32-) ions. Two prominent approaches are:

Raising the ocean's alkalinity not only bolsters its CO2 uptake capabilities but also acts as a counterbalance to the acidification stemming from excess human-generated CO2 emissions.

Since natural processes like mineral weathering and oceanic alkalinity generation are key mechanisms through which the environment absorbs and retains CO2, investigating these strategies is certainly worth consideration.

It's important to note that while these methods show potential for addressing ocean acidification and assisting in CO2 removal, they entail potential environmental, chemical, and technical challenges.

Any large-scale intervention within marine ecosystems necessitates careful assessment of its ecological impacts and feasibility. Additionally, these approaches should be viewed as components of a comprehensive strategy to combat climate change and its associated impacts.

3. Strengthening coastal ecosystems

Efforts to rejuvenate coastal ecosystems play a pivotal role in addressing the impacts of environmental degradation. Restoration endeavors provide innovative pathways to heal damaged ecosystems.

Ecologists are pioneering techniques such as creating artificial habitats and implementing assisted breeding methods to reinvigorate biodiversity.

Furthermore, strategies like restoring natural river flows and reconnecting rivers to floodplains, coupled with curbing coastal runoff, contribute to the recovery of these crucial ecosystems.

The restoration and preservation of coastal vegetation, including saltmarshes, mangroves, and seagrasses (referred to as "blue carbon ecosystems"), are aimed at amplifying their capacity as carbon sinks and averting emissions from their substantial carbon reservoirs if they degrade or vanish.

This strategy is contemplated on a global scale, assuming the theoretical revival and safeguarding of worldwide habitats damaged by human activity.

Additionally, it is embraced locally, offering localized benefits in terms of mitigation and adaptation, along with other positive outcomes.

Bringing such projects to fruition often hinges on securing funds from diverse sources, including grants and community-driven initiatives.

By nurturing collaborative partnerships and financial support, we can nurture the growth and resilience of coastal ecosystems, paving the way for a healthier and more sustainable future.

4. Monitoring human activities

Effective monitoring of human activities is essential to ensure the sustainability of our oceans.

Governments have a crucial role in guaranteeing sustainable practices within the seafood industry through the enforcement of regulations that curb overexploitation.

Steps like instituting catch limits and discontinuing subsidies significantly contribute to this endeavor. Additionally, they can establish coastal protective zones to mitigate the impacts of flooding and erosion.

Addressing overexploitation involves ensuring that the extraction and harvesting of living resources remain within biologically sustainable limits for human use, thereby maintaining both ecosystem functionality and, in the case of non-living resources like minerals and sand, preventing irreversible ecological damage.

In ecosystems that are heavily exploited, you often see smaller and faster-reproducing species of fish becoming more dominant. These species tend to thrive when environmental conditions are favorable.

In contrast, larger bottom-dwelling fish, known as demersal fishes, are often depleted in such ecosystems.

Consequently, fisheries that witness a shift towards pelagic species dominance tend to exhibit greater sensitivity to climate-induced environmental changes.

While species with higher turnover rates theoretically possess a greater capacity for evolutionary adaptation to environmental shifts, the actual extent and speed of such adaptive responses in most fish species remain uncertain.

Moreover, fish stocks depleted due to overexploitation may suffer from reduced genetic diversity and variability. As a result, these populations might have limited potential for adaptation in the face of climate change.

Furthermore, the development of innovative monitoring tools can be instrumental in predicting and managing outbreaks of marine diseases.

These combined efforts can play a pivotal role in safeguarding the health and resilience of our marine ecosystems and coastal regions.

5. Enhancing scientific research

The urgency of addressing ocean warming and its far-reaching consequences demands a robust and concerted effort in scientific research.

In our pursuit to counteract the concerning trajectory of ocean warming, the significance of knowledge cannot be overstated.

Governments have the opportunity to enhance their investments in scientific research aimed at quantifying and overseeing oceanic warming and its consequences.

This initiative would yield more accurate and comprehensive information regarding the extent, characteristics, and repercussions of oceanic warming, thereby facilitating the formulation and execution of effective and fitting strategies for both mitigating and adapting to these changes.

Here's why scientific research is a cornerstone in our battle against ocean warming:

6. Solar Radiation Management (SRM)

Solar radiation management (SRM), also referred to as sunlight reflection methods, aims to augment the Earth's albedo, either within the atmosphere or at the surface, with the intention of increasing the fraction of solar energy that is deflected back into space. This approach encompasses TWO primary ocean-based strategies.

Marine Cloud Brightening

Marine Cloud Brightening entails the widespread dispersion of seawater or other compounds into the lower atmosphere. This process is intended to enhance the light-reflecting capabilities of clouds, thereby amplifying their ability to reflect sunlight.

Surface Ocean Albedo Enhancement

Surface Ocean Albedo Enhancement, on the other hand, would involve generating enduring micro-bubbles or foam at the ocean's surface. The objective here is to raise the albedo of the ocean surface, consequently intensifying the reflection of solar radiation.

Both of these methods are proposed as potential techniques for mitigating the impacts of climate change by influencing the Earth's energy balance through modifying its reflective properties.

However, the feasibility, effectiveness, and potential consequences of these strategies remain subjects of intense scientific investigation and ethical deliberation.

7. Adoption of green tech

The ocean serves as a pivotal reservoir for heat absorption, effectively taking in and storing a significant proportion of the surplus heat resulting from human-driven climate alterations.

Over the course of the last half-century, the primary locus of global warming has been the Earth's oceans, contributing to more than 90 percent of the overall warming phenomenon.

In response, the International Maritime Organization (IMO) has instituted more stringent benchmarks, catalyzing comprehensive research and the advancement of environmentally friendly technologies within the maritime sector.

Acknowledging the imperative for transformation, the shipping sector is also progressively integrating environmentally conscious technologies and redefining its practices.

The challenge of ocean warming calls for a multidimensional approach, and green technologies are proving to be valuable tools in our efforts to combat this critical issue. These innovative solutions offer promising avenues to mitigate the impacts of ocean warming and contribute to a more sustainable future for our planet.

8. Relocation and Reef Restoration

Relocation and reef restoration encompass the revitalization of deteriorated coral and oyster reefs, alongside the potential establishment of novel habitats that support species with higher resilience to environmental challenges.

Reef restoration

This encompasses a range of activities aimed at rehabilitating damaged or degraded coral reefs.

Techniques include coral gardening, where coral fragments are grown in nurseries and then planted onto the reef.

Moreover, coral micro-fragmentation, where small coral pieces are broken down and allowed to grow into full-sized colonies; and artificial structures like coral frames or reef balls, which provide substrate for corals to settle and grow.

These strategies are employed to combat the effects of coral bleaching, ocean acidification, and other stressors that threaten the survival of coral reefs. They aim to rebuild and strengthen coral populations, enhance biodiversity, and improve the overall health of reef ecosystems.

However, the success of these methods depends on various factors, including the selection of suitable species, proper site assessment, ongoing monitoring, and consideration of local ecological conditions.