在阿拉斯加亚北极地区的全新世纪气候周期变化和太阳强迫
Feng Sheng Hu1, Darrell Kaufman, Sumiko Yoneji
1Department of Plant Biology, University of Illinois, Urbana, IL 61801, USA. fshu@life.uiuc.edu
概括
阿拉斯加的Holocene气候显示了与太阳活动相关的周期变化. 这些太阳能驱动的变化影响了北方的生态系统,并暗示了北大西洋和北太平洋的类似气候变化.
科学领域:
- 古气候学 古气候学
- 四年纪地质学四年纪地质学
- 气候科学 气候科学
背景情况:
- 全新世气候变化对于理解地球气候系统至关重要.
- 高度地区是全球气候变化的敏感指标.
- 太阳能活动对区域气候的影响仍然是一个活跃的研究领域.
研究的目的:
- 研究阿拉斯加西南部的全新纪气候和生态系统动态.
- 确定气候变化的周期性及其与太阳活动的相关性.
- 为了比较北大西洋和北太平洋地区的Holocene气候变化.
主要方法:
- 高分辨率分析阿拉斯加西南部湖泊沉积物核心.
- 频谱分析以确定周期变化和周期性.
- 与宇宙原核化物 (碳-14和-10) 和北大西洋漂流冰的时间序列的相关性分析.
主要成果:
- 湖泊沉积物记录揭示了Holocene期间明显的周期性气候和生态系统变化.
- 这些变化表现出与太阳活动周期一致的周期性.
- 在阿拉斯加气候数据,宇宙原核记录和北大西洋漂流冰数据之间观察到一致性.
结论:
- 太阳辐射的变化显著影响了北方高度地区的全新纪气候和生态系统.
- 亚极北大西洋和北太平洋的百年级气候变化是同步的.
- 太阳-海洋-气候联系可能在同步这些半球气候变化方面发挥了关键作用.
相关概念视频
What is Climate?
Climate refers to the prevailing weather conditions in a specific area over an extended period. As the saying goes, “Climate is what you expect. Weather is what you get.” Climate is influenced by geographic factors, such as latitude, terrain, and proximity to bodies of water.
Global Climate Change
Throughout its ~4.5 billion year history, the Earth has experienced periods of warming and cooling. However, the current drastic increase in global temperatures is well outside of the Earth’s cyclic norms, and evidence for human-caused global climate change is compelling. Paleoclimatology, the study of ancient climate conditions, provides ample evidence for human-caused global climate change by comparing recent conditions with those in the past.
Biological Clocks and Seasonal Responses
The circadian—or biological—clock is an intrinsic, timekeeping, molecular mechanism that allows plants to coordinate physiological activities over 24-hour cycles called circadian rhythms. Photoperiodism is a collective term for the biological responses of plants to variations in the relative lengths of dark and light periods. The period of light-exposure is called the photoperiod.
Cyclic Processes And Isolated Systems
A thermodynamic system with zero heat exchange and work is an isolated system. For these systems, the internal energy remains constant.
In the case of a non-isolated system, the change in the internal energy is zero only if the process is cyclic. A thermodynamic process is considered cyclic if the system undergoes a series of changes and returns to its initial state.
Consider a cyclic process that returns to its initial state, undergoing a four-step process. The heat transfer along each path...
In the case of a non-isolated system, the change in the internal energy is zero only if the process is cyclic. A thermodynamic process is considered cyclic if the system undergoes a series of changes and returns to its initial state.
Consider a cyclic process that returns to its initial state, undergoing a four-step process. The heat transfer along each path...
Variation of Atmospheric Pressure
Change in atmospheric pressure with height is particularly interesting. The decrease in atmospheric pressure with increasing altitude is due to the decreasing gravitational force per unit area as we move away from the surface of the earth.
Assuming the air temperature is constant at a given altitude and that the ideal gas law of thermodynamics describes the atmosphere to a good approximation, one can find the variation of atmospheric pressure with height.
Let p(y) be the atmospheric pressure at...
Assuming the air temperature is constant at a given altitude and that the ideal gas law of thermodynamics describes the atmosphere to a good approximation, one can find the variation of atmospheric pressure with height.
Let p(y) be the atmospheric pressure at...
Microbes and Climate Change
Microorganisms are pivotal agents in Earth's biogeochemical cycles, significantly influencing climate dynamics through their metabolic activities. These microbes modulate the levels of key greenhouse gases by both contributing to and helping mitigate climate change.Microbial Contributions to Greenhouse Gas EmissionsRising global temperatures accelerate microbial metabolism, which, in turn, speeds up the decomposition of organic matter. This process releases carbon dioxide (CO₂) through...


