混合相雲の観測上の制約は,より高い気候感受性を意味しています
Ivy Tan1, Trude Storelvmo2, Mark D Zelinka3
1Department of Geology and Geophysics, Yale University, New Haven, CT 06511, USA. ivy.tan@yale.edu.
Science (New York, N.Y.)
|April 29, 2016
まとめ
混合相雲を正確にシミュレートすると,グローバル気候感度 (ECS) の推定値が増加します. これは,より暖かい気候における雲の氷化が遅いことに関連した弱まった雲相フィードバックによるものです.
科学分野:
- 気候科学
- 大気物理学
- 雲の微物理
背景:
- グローバル気候モデル (GCM) は,CO2が2.0°Cから4.6°Cの間に倍増した場合の均衡気候感度 (ECS) を推定しています.
- 雲はこれらのECS予測の主要な不確実性の源です.
- 混合相雲は 氷の結晶と 超冷却液滴を含んでおり 気候フィードバックに 重要な役割を果たします
研究 の 目的:
- ECSの見積もりに対する現実的な混合段階のクラウド表現の影響を調査する.
- 気候感受性に対する雲相フィードバックの影響を定量化する.
主な方法:
- 混合相雲の地球衛星観測を用いた GCM シミュレーションの制限
- 雲の結氷率と気候の感受性の関係を分析する
主要な成果:
- 衛星による混相雲によるシミュレーションでは,ECSの推定値は最大1.3°C上昇した.
- 高いECSは弱まったクラウドフェーズフィードバックに関連しています.
- 暖かい気候における雲の結氷率の低下は,フィードバックの弱まりに寄与する.
結論:
- 混合相雲における超冷却液体の正確な表現は,GCMにとって極めて重要です.
- クラウド・フェーズ・フィードバックはECSに大きな影響を及ぼし,さらなる調査が必要である.
- 衛星による制約により,気候感受性予測の信頼性が向上します.
関連する概念動画
01:50Global Climate Change
29.6K
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.
29.6K
01:16What is Climate?
21.3K
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.
21.3K
01:12Precipitation Processes
6.5K
The experimental conditions in a gravimetric analysis should be optimized to maximize the particle size and purity of the obtained precipitate. Ideally, the concentration of the precipitating reagent should be low with effective stirring to maintain low relative supersaturation for the growth of large crystals. In homogeneous precipitation, the precipitant is slowly generated by a chemical reaction in the solution to avoid local reagent excesses. For example, urea decomposes gradually to...
6.5K
01:27Microbes and Climate Change
15
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...
15
01:17Precipitation and Co-precipitation
5.5K
Precipitation and coprecipitation methods can be used to separate a mixture of ions in a solution. In qualitative inorganic analysis, ions that form sparingly soluble precipitates with the same reagent are separated based on the differences in solubility products. For example, consider the separation of Cu(II) and Fe(II) ions by precipitation as insoluble sulfides. First, copper(II) sulfide is precipitated by the addition of acidic H2S, where the dissociation of H2S is suppressed. Adding H2S...
5.5K
02:39Phase Transitions: Vaporization and Condensation
22.0K
The physical form of a substance changes on changing its temperature. For example, raising the temperature of a liquid causes the liquid to vaporize (convert into vapor). The process is called vaporization—a surface phenomenon. Vaporization occurs when the thermal motion of the molecules overcome the intermolecular forces, and the molecules (at the surface) escape into the gaseous state. When a liquid vaporizes in a closed container, gas molecules cannot escape. As these gas phase molecules...
22.0K