The ecoregion occupies a vast, flat lowland east of the northern Ural Mountains, defined by water on nearly every side. The Ob River's delta and Gulf of Ob bound it to the west; the Yenisei estuary marks its eastern edge. To the north lies the Kara Sea, a marginal basin of the Arctic Ocean, and several offshore islands -- including Bely Island at the Yamal Peninsula's tip -- fall within the ecoregion's boundaries. The terrain is relentlessly flat. Extensive wetlands fill the spaces between low hummocks of moss and lichen, and the entire area sits within the zone of continuous permafrost. There are no mountains, no significant elevation changes, no natural windbreaks. What the landscape offers instead is space -- a horizon so distant it curves, and a sky that, during the brief summer, fills with birds.

The tundra here is not uniform but assembled in irregular mosaics. Hummocky lichen-moss patches alternate with shrub-moss zones, separated by bare ground and saturated wetlands. In the northern reaches, lichen tundra and exposed soil dominate, the vegetation sparse enough that individual plants seem to crouch against the wind. Farther south, a thin grass-shrub layer emerges among the lichen-moss communities, though "grass" here means something quite different from temperate meadowland -- low, tough, and scattered. Spring floods reshape the marshes annually, fed by snowmelt that has nowhere to drain through the frozen ground beneath. Autumn rains waterlog the sedge marshes again before winter seals everything under snow. The growing season is desperately short, lasting only the one to three months when average temperatures rise above 10 degrees Celsius, and no month exceeds 22 degrees.

An estimated 50 species of birds nest in the Yamal-Gydan tundra, making it a vital node on the Atlantic flyway. Waterfowl, waders, and seabirds converge here during the brief Arctic summer to breed on the wetlands and coastal flats, then disperse southward along migration routes that stretch to western Europe and Africa. The mammalian roster is far shorter. Arctic foxes hunt lemmings across the hummocks, their populations rising and crashing in tandem with the famous lemming cycles. Small herds of reindeer graze the tundra, remnants of the larger populations managed by Nenets herders on the Yamal side. The climate is classified as humid continental with cool summers -- long, freezing winters that average well below zero in January, and summers that barely touch 10.5 degrees Celsius at the ecoregion's center. Mean precipitation is about 514 millimeters per year, much of it falling as snow that blankets the ground for the majority of the year.

For an ecoregion the size of a mid-sized European country, formal protection is remarkably thin. The Gydan Nature Reserve, located on the Gyda Peninsula's northern tip, is the single significant nationally protected area within the entire ecoregion. Established in 1996 and converted to national park status in 2019, it covers the peninsula's most northerly terrain and several offshore islands but represents only a fraction of the broader ecoregion. The rest is technically unprotected, though its remoteness has functioned as a de facto shield. That shield is weakening. Oil and gas exploration has expanded across both peninsulas, with industrial infrastructure cutting into previously undisturbed tundra. The permafrost that underpins the entire landscape is warming, destabilizing the ground and releasing methane. For the migratory birds that depend on these wetlands as breeding habitat, the question is how much change the ecosystem can absorb before the nesting grounds that have drawn them here for millennia are no longer recognizable.