The oceans are warming: why this also affects our garden

When we talk about climate change, the focus is often on air temperatures. We look at thermometers, observe heatwaves, and record new summer records. Yet there is another indicator that is even more important for understanding what is happening to the planet: ocean temperatures.

In recent years, the scientific community has observed a continuous increase in the heat stored by the world's seas. According to numerous international studies, the oceans are accumulating energy at an unprecedented rate in modern measurementse, becoming a kind of archive of the climate crisis.

At first glance, it may seem like a phenomenon far removed from daily life. In reality, what happens in the oceans directly influences the climate of our cities, our countryside, and even our gardens.

• The planet's great heat reservoir
• Why warmer seas mean more extreme weather
• Ecosystems under pressure
• What does all this have to do with gardening?

The planet's great heat reservoir

The oceans cover over 70% of the Earth's surface and play a fundamental role in the global climate system. One of their most important functions is to absorb much of the excess heat produced by the increase in greenhouse gases in the atmosphere.

According to the most reliable estimates, over 90% of the additional energy retained by the Earth's climate system is stored in the oceans. If this enormous absorption did not occur, air temperatures would already be much higher than they are today. In a sense, the seas are slowing down the warming of the planet. But this "service" comes at an increasingly evident cost: year after year, the water accumulates thermal energy and alters global climate balances.

Why warmer seas mean more extreme weather

Warm water evaporates more easily. When ocean surfaces reach high temperatures, the amount of water vapor in the atmosphere increases. This phenomenon can result in more intense precipitation, violent thunderstorms, and flash floods. This is one of the reasons why an apparent contradiction is observed in many regions of the world: increasingly long periods of drought alternating with heavy rainfall concentrated in just a few hours.

A warmer atmosphere is thus able to hold greater amounts of moisture and, when conditions become favorable, releases this energy in the form of extreme weather events. In recent years, the Mediterranean has provided several examples of this dynamic, with episodes of exceptional precipitation alternating with long periods without rain. In fact, among all the regions of the world, scientists consider the Mediterranean basin one of the main climate change hotspots.

In fact, our sea is warming faster than the global average and has characteristics that make it particularly vulnerable: being relatively enclosed, it reacts more quickly to temperature increases than open oceans.

The consequences do not only affect the marine environment. Higher water temperatures influence the formation of disturbances, alter precipitation patterns, and contribute to an increase in the frequency of land heatwaves. In other words, the sea that bathes our coasts directly participates in shaping the climate we experience every summer.

Ecosystems under pressure

The warming of the waters represents an important challenge for biodiversity as well.

Many marine species are adapted to relatively stable temperature ranges. When these limits are exceeded, ecosystems suffer. Some species migrate to cooler areas, others struggle to survive, and new species from warmer regions begin to colonize territories they could not have occupied in the past.

In the Mediterranean, these changes are already observable. Scientists have been recording the arrival of tropical and subtropical species for years, while some organisms typical of temperate waters show signs of distress.

Phenomena such as ocean acidification and the decrease in dissolved oxygen also contribute to making ecosystems more fragile.

What does all this have to do with gardening?

More than you might imagine.

The changes we observe in our gardens are often the local manifestation of processes occurring on a global scale. Longer summers, more frequent heatwaves, irregular precipitation, and intense rainfall events are all phenomena also influenced by the progressive warming of the oceans. For this reason, the way green spaces are designed is changing.

The selected plants must be able to cope with longer periods of drought. The soil must become capable of retaining available moisture more effectively. Biodiversity plays an increasingly important role in maintaining ecological balances. In this context, Mediterranean gardens and alternative lawns represent a concrete response to a climate that is no longer what it was a few decades ago.

Research on ocean warming reminds us that climate change is neither an abstract nor distant phenomenon. It is a process that affects the entire planet and manifests itself through a long chain of interconnected effects. The sea absorbs heat, the atmosphere retains more moisture, extreme events become more frequent, and ecosystems must adapt to new conditions. Even the garden, in its own small way, is part of this transformation.

Designing more resilient green spaces, using species suited to the Mediterranean climate, improving soil health, and reducing dependence on irrigation does not only mean saving water or maintenance. It means learning to live with a changing environment and building landscapes capable of facing the challenges of the coming decades.