Sökning: "climate variability"
Visar resultat 16 - 20 av 272 avhandlingar innehållade orden climate variability.
16. Greenhouse gas emission from tropical reservoirs : Spatial and temporal dynamics
Sammanfattning : The emission of methane (CH4) and carbon dioxide (CO2) from reservoirs has been estimated to make up for about 1.3% of the global anthropogenic greenhouse gas emission. The impoundment of a river leads to the accumulation of sediment that is brought in from inflowing rivers, and the sediment organic matter is degraded to CH4 and CO2. LÄS MER
17. Methane dynamics in northern lakes : Insights from multi-scale observations
Sammanfattning : Methane (CH4) is a potent greenhouse gas which is emitted to the atmosphere from both natural and anthropogenic sources. Current evidence indicates that lakes account for a large part of the global emissions of CH4, but their contribution is difficult to quantify because of large temporal and spatial variability in processes leading to CH4 fluxes from lakes to the atmosphere. LÄS MER
18. On the Arctic Seasonal Cycle
Sammanfattning : The seasonal cycle of snow and sea ice is a fundamental feature of the Arctic climate system. In the Northern Hemisphere, about 55 million km2 of sea ice and snow undergo complete melt and freeze processes every year. LÄS MER
19. Changes in near-surface winds across Sweden over the past decades - Observations and simulations
Sammanfattning : Driven by a combination of anthropogenic activities and climate changes, near- surface terrestrial winds displayed a large decrease in their magnitude in the past decades, named “stilling”, and a recent recovery in their slowdown. Understanding how wind has changed and identifying the factors behind the observed variabilities is crucial so that reasonable future wind scenarios can be constructed. LÄS MER
20. Surface energy exchange and land-atmosphere interactions of Arctic and subarctic tundra ecosystems under climate change
Sammanfattning : The surface energy balance determines the functioning of any ecosystem on the Earth but is still poorly understood in Arctic and subarctic biomes. In a dynamic system, such as the Earth’s climate, any change in its characteristics modifies the exchange of energy, water, and greenhouse gases between the surface and the atmosphere. LÄS MER
