Costa Rica’s Thermal Dome has just formed
Dive this natural phenomenon with Cookson Adventures
February 2026: The Cookson Adventures team has identified the formation of the blink-and-you’ll-miss-it Thermal Dome over 100 nautical miles off Costa Rica’s Pacific Coast – and has an expert team ready in place for clients who want to chase one of the ocean’s rarest spectacles.
This elusive natural phenomenon has been witnessed by only a privileged few as it requires expert research and precision on-the-ground logistics. Guests can only experience it in a short time window, as the location where the Dome forms changes in diameter and position every year making it incredibly difficult to predict in advance.
The Thermal Dome describes a powerful upwelling of cold, nutrient-rich deep waters, which creates an explosion of algae and plankton, that in turn draws an astonishing concentration of marine species into a single, electrifying arena. For those who find it at the right time, it becomes one of the most intense marine encounters on Earth.
Finding it requires constant analysis of oceanographic data, wind patterns, and real-time aerial observation using spotter planes and helicopters to pinpoint its precise location and peak activity.
When the best moment arrives, Cookson Adventures will transfer guests offshore into a fast boat or private yacht so they can reach it and get into the water alongside the marine life for a truly spectacular diving experience. There are no fixed dive sites, no markers, no infrastructure. Just beneath the surface, the open ocean fills with life. Divers and snorkellers may find themselves drifting alongside blue whales, giant manta rays, sea turtles and vast schools of sharks – gathering in concentrations seldom encountered anywhere on the planet.
The private group can be supported by expert diving instructors, researchers and professional underwater photographers to document this fleeting moment few will ever witness.
These expeditions can be combined with scientific research – from tagging programmes and acoustic monitoring to survey dives, educational briefings and photoID work that supports long-term conservation.
Harry Rowe-Pereira, Head of Private Clients at Cookson Adventures comments; “This has the potential to be one of the most extraordinary wildlife experiences on the planet. Its remoteness and sheer unpredictability has protected the event from the pressures of mass tourism, preserving a marine spectacle that very few people have ever witnessed. It’s difficult to convey just how dynamic and elusive the Costa Rica Thermal Dome is. The conditions have to be so precise before even entertaining the idea of trying to find it, though, excitingly, as we know it has now formed, we’ve had interest from a client and are building out a Costa Rican adventure by private yacht and support vessel, with the lure of this elusive spectacle as the ultimate extension.
The moment conditions align; we will have an advanced team ready to mobilise and place them directly into one of the rarest wildlife encounters on Earth”.
Cookson Adventures can frame this experience within a wider action-filled Costa Rican journey, staying at a coastal retreat or chartering a purpose-built explorer yacht.
HOW: Cookson organises yacht and land-based trips to Costa Rica from £150,000 for a week filled with unique experiences and expert hosts, alongside bespoke itinerary planning.
For all media enquiries or for more information, interviews or images please contact Tamsin Graham on [email protected]
[email protected]About Cookson Adventures
Since 2007, Cookson Adventures has been redefining what it means to explore the world. As pioneers of the “world-first” in luxury adventure travel, they’ve taken bold steps into the unknown — from orchestrating the first private submersible dive in Antarctica to leading hands-on conservation projects across Africa and the Galápagos Islands.
The Founder and Chairman is Henry Cookson – a dedicated adventurer and Guinness World Record holder for reaching the Southern Pole of Inaccessibility, the most remote point on the Antarctic continent. Guided by his spirit of discovery, Cookson’s expert team designs journeys that blend the thrill of exploration without ever compromising on comfort or safety.
Each expedition is crafted from the ground up, fusing explorer yachts, helicopters, submersibles, opulent celebrations, and bespoke camps set in some of the planet’s most untouched corners. Supported by a global network of scientists, marine biologists, conservationists, and award-winning photographers, each adventure invites guests to venture deeper, see further, and experience the extraordinary.
