Ecosystems
Coral Reef Bleaching: Causes & Impact
Understand the science behind mass bleaching events and what they mean for marine biodiversity.
The Ocean Guide
Your comprehensive hub for marine education, ocean science, and swimming knowledge.
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Explore by Topic
Six interconnected areas covering the full scope of ocean science and swimming practice.
Ocean Basics
Understanding Our Blue Planet
Key concepts that form the foundation of ocean literacy.
5
Major ocean basins: Pacific, Atlantic, Indian, Southern, and Arctic. The Pacific alone covers more area than all land masses combined.
230K+
Known marine species — but scientists estimate the true number could be over 2 million, with most of the ocean still unexplored.
90%
of the ocean is deep sea — below 200 meters — remaining largely unexplored and mysterious to this day.
1°C
rise in ocean temperature can trigger coral bleaching. The ocean has absorbed over 90% of excess heat from climate change.
Deep Dives
Essential Reading
Our most comprehensive guides for understanding the ocean and swimming in it.
Safety
Reading Tides, Currents & Rip Tides
The essential knowledge every ocean swimmer needs before entering the water.
Pollution
The Great Pacific Garbage Patch
What it actually is, how it formed, and why cleanup is so challenging.
Marine Life
Overfishing & Sustainable Seafood
Which fish populations are recovering, which are collapsing, and how to choose wisely.
Climate
Individual Actions & Ocean Health
How everyday choices — from diet to laundry — affect the ocean.
Quick Reference
Ocean Health Indicators
Scientists track several key indicators to assess the overall health of our oceans. Here are the most important ones:
Sea Surface Temperature (SST)
Rising SST drives coral bleaching, shifts marine species ranges, and intensifies storms. The global average has increased by about 0.88°C since 1900.
Ocean Acidification
The ocean absorbs about 30% of CO2 emissions, lowering its pH. Since the Industrial Revolution, surface water pH has dropped from 8.2 to 8.1 — a 30% increase in acidity.
Plastic Concentration
An estimated 171 trillion plastic particles float in the ocean. Without action, this number could triple by 2040.
Marine Biodiversity Index
The Living Planet Index for marine species has declined by 36% since 1970. Coral populations have fallen by 50% in the same period.
Dead Zones
Ocean dead zones — areas with too little oxygen to support life — have quadrupled since 1950. There are now over 700 worldwide.