adjacent to composed primarily of surface layer atmosphere snow hoar depth hoar 2020-02-12T20:58:41Z Depth hoar is associated with very fast crystal growth under large temperature gradients. Sometimes a layer of depth hoar forms just above, and may assist in identifying the summer surface. The low density and low strength of depth hoar can make it difficult to retrieve unbroken core sections during coring, and can complicate estimates of accumulation by microwave remote sensing. Layers of depth hoar also increase the likelihood of avalanching. This is one way in which firn formation may begin. Depth hoar is similar in physical origin to crevasse hoar. Hoar which is usually cup-shaped and facetted and which forms within dry, low-density snow beneath the snow surface.