Climatologist Dr. Elena Rostova and her team investigated how geothermal heat flux under the West Antarctic Ice Sheet influences glacial sliding velocity. Rostova hypothesized that local geothermal hot spots liquefy the basal ice layer, creating a thin film of water that lubricates the interface between the ice and bedrock, thereby accelerating glacier flow toward the ocean independently of atmospheric temperature shifts.
Which finding, if true, would most directly support Rostova's hypothesis?
- AGlaciers in areas with low geothermal heat flux have shown a minor increase in sliding velocity over the past decade, which corresponds with a documented rise in average summer air temperatures in those areas.
- BBasal water samples retrieved from geothermally active regions show higher salinity levels than those from inactive regions, suggesting that subglacial volcanic activity prevents the formation of a lubricating liquid layer.
- Glaciers situated directly above active geothermal anomalies flow toward the ocean at much higher velocities than neighboring glaciers situated over geothermally inactive bedrock, despite both groups of glaciers experiencing the same sub-zero atmospheric temperatures.Answer
- DGeothermal hot spots under the West Antarctic Ice Sheet are projected to double in size over the next century, eventually leading to the complete destabilization of the entire ice sheet.
Answer
The finding that glaciers situated above active geothermal anomalies flow faster than neighboring glaciers under identical atmospheric temperatures.
The finding that glaciers above geothermal anomalies slide faster under the same air temperatures directly supports the hypothesis. It isolates geothermal heat as the causal factor for the acceleration, confirming that it operates independently of atmospheric warming.
Step-by-Step Solution
Key Concept
Identifying textual evidence that supports a scientific hypothesis by establishing logical relationships between variables.
Estimated Time:1m 30s