Oceans and climate

Summary

The script highlights the critical role of oceans as vast heat reservoirs, absorbing 93% of excess heat from human activities over 70 years. Ocean currents, driven by winds and water density differences, redistribute heat globally, influencing weather and climate. Europe's mild climate is attributed to the Gulf Stream. Ocean heat waves can cause coral bleaching and habitat loss. Oceans also absorb CO2, leading to acidification and threatening marine life. Satellites monitor various ocean variables, including sea level, salinity, and ice cover, which are crucial for understanding climate regulation and the impacts of climate change on our oceans.

Takeaways

• 🌊 Oceans act as vast heat reservoirs, absorbing 93% of the excess heat from human activity over the past 70 years.
• 🔄 Ocean currents play a vital role in redistributing heat globally, with surface currents driven by winds and deep currents by water density differences due to temperature and salinity.
• 🌡️ The distribution of ocean heat influences weather patterns and regional climates, exemplified by Europe's mild climate due to the warm Gulf Stream and North Atlantic Current.
• 🌡️ Ocean heat waves can have detrimental effects, such as coral bleaching, habitat loss, and the absorption of heat by oceans.
• 🌿 Oceans also serve as a natural carbon sink, absorbing about a quarter of carbon dioxide emissions from human activity, leading to ocean acidification and threats to marine life.
• 🔬 The amount of heat and carbon dioxide absorbed by oceans depends on various factors including phytoplankton, temperature, waves, salinity, and ice cover, all of which can be monitored from space.
• 🛰️ Satellites are capable of measuring sea level and slope, allowing for the derivation of surface currents.
• 🌧️ Ocean salinity maps reveal regions of evaporation, precipitation, and river inflow, with high salinity in enclosed basins like the Mediterranean Sea due to high evaporation.
• ❄️ Ocean salinity increases in areas where sea ice forms, as salt is left behind when water freezes, contributing to the thermo-haline circulation.
• 🌀 The thermo-haline circulation is essential for global climate regulation and drives surface currents like the Gulf Stream.
• ☁️ There are signs that the thermo-haline overturning in the North Atlantic is weakening, which could lead to cooler air over Europe and more winter storms, as well as higher sea levels and more powerful hurricanes along the Atlantic coast of North America.
• 🌍 East's climate change initiative is generating long-term datasets to understand the influence of oceans on climate and the impact of climate change on our oceans.

Q & A

What role do oceans play in storing heat from human activity?

Oceans act as massive heat stores, having absorbed 93% of the excess heat from human activity over the past 70 years.

How do ocean currents redistribute heat around the planet?

Ocean currents redistribute heat from the equator to the poles, with surface currents primarily driven by winds and deep currents caused by differences in water density due to temperature and salinity.

Why is Europe's climate mild?

Europe's mild climate is attributed to the warm Gulf Stream and North Atlantic Current, which transport warm water from the equator to higher latitudes.

What are the consequences of ocean heat waves on marine life?

Ocean heat waves can lead to coral bleaching, habitat loss, and other detrimental effects on marine ecosystems.

How do oceans act as a carbon sink and what is the impact of this on ocean water?

Oceans absorb about a quarter of carbon dioxide emissions from human activity, which has led to the acidification of ocean water, threatening marine life.

What factors determine the amount of heat and carbon dioxide absorbed by oceans?

The amount of heat and carbon dioxide absorbed by oceans depends on variables such as phytoplankton, temperature, waves, salinity, and ice cover.

How can satellites measure and monitor ocean conditions from space?

Satellites can measure sea level, slope, and salinity, from which surface currents and regions of evaporation, precipitation, and river inflow can be derived.

Why does the Mediterranean Sea have high salinity?

The Mediterranean Sea has high salinity due to high evaporation rates in its enclosed basin, leaving behind salt as water evaporates.

What is the thermo-haline circulation and why is it important for global climate regulation?

The thermo-haline circulation is a centuries-long journey of cold, salty, dense water sinking into the ocean's depths, which is crucial for regulating global climate and driving surface currents like the Gulf Stream.

What signs indicate that the overturning in the North Atlantic is weakening, and what could be the consequences?

There are signs that the North Atlantic's overturning is weakening, which could lead to cooler air over Europe, more winter storms, and potentially higher sea levels, warmer waters, and more powerful hurricanes along the Atlantic coast of North America.

How is East's climate change initiative contributing to our understanding of oceans and climate?

East's climate change initiative is producing long-term data sets that help us understand how oceans influence climate and how the changing climate is affecting our oceans.