| Term | Definition | Contributor | Modified |
|---|---|---|---|
| Blizzard | A severe weather condition characterized by high winds and reduced visibilities due to falling or blowing snow. The U.S. National Weather Service specifies sustained wind or frequent gusts of 16 m per second (30 kt or 35 mi per hour) or greater, accompanied by falling and/or blowing snow, frequently reducing visibility to less than 400 m (0.25 mi) for 3 hours or longer. Earlier definitions also included a condition of low temperatures, on the order of -7C (20F) or lower, or -12C (10F) or lower (severe blizzard). The name originated in the United States but it is also used in other countries. In the Antarctic the name is given to violent autumnal winds off the ice cap. In southeastern France, the cold north wind with snow is termed blizzard (see also boulbie). Similar storms in Russian Asia are the buran and purga. In popular usage in the United States and in England, the term is often used for any heavy snowstorm accompanied by strong winds. | GCW Glossary | 2023.03.27 |
| Blizzards | No definition provided | Christopher Rauch | 2023.12.01 |
| BL Lacertae objects | No definition provided | Ryan McGranaghan | 2023.04.16 |
| block | Angular chunk of solid rock ejected during an eruption. | Ryan McGranaghan | 2023.04.16 |
| Blockade | No definition provided | Christopher Rauch | 2023.12.01 |
| Blockade, Pacific | No definition provided | Christopher Rauch | 2023.12.01 |
| Blockade running | No definition provided | Christopher Rauch | 2023.12.01 |
| Block-books | No definition provided | Christopher Rauch | 2023.12.01 |
| Blockbooks | No definition provided | Christopher Rauch | 2023.12.01 |
| Block-books--Facsimiles | No definition provided | Christopher Rauch | 2023.12.01 |
| Block field | A surficial layer of angular shattered rocks formed in either modern or Pleistocene periglacial environments | GCW Glossary | 2023.03.27 |
| blocking | No definition provided | Ryan McGranaghan | 2023.04.16 |
| blocking index | No definition provided | Ryan McGranaghan | 2023.04.16 |
| Blockite | No definition provided | Ryan McGranaghan | 2023.04.16 |
| Block-signal systems | No definition provided | Christopher Rauch | 2023.12.01 |
| Blocky iceberg | Sea ice terminology that describes a flat-topped iceberg with steep vertical sides. | GCW Glossary | 2023.03.27 |
| Blodite | No definition provided | Ryan McGranaghan | 2023.04.16 |
| Bloedite | No definition provided | Ryan McGranaghan | 2023.04.16 |
| Blomstrandite | No definition provided | Ryan McGranaghan | 2023.04.16 |
| Blood | No definition provided | Christopher Rauch | 2023.12.01 |