科学创新正在颠覆传统的森林范式,水,和能量循环相互作用。这对我们理解树的主要因果途径有影响,森林,和植被覆盖(TFVC)影响局部和全球变暖/降温。许多人认为地表反照率和碳封存是TFVC影响全球变暖/变冷的主要因果途径。向外纬度移动,特别是,在积雪更重要的地方,表面反照率效应被认为超过了碳固存。通过提高地表反照率,因此,预计森林砍伐会导致地表冷却,而增加森林覆盖率被认为会导致变暖。观测数据,然而,一般支持相反的结论,表明地表反照率知之甚少。大多数人接受表面温度受表面反照率相互作用的影响,输入短波(SW)辐射,以及其余的分区,后反照率,SW辐射转化为潜热和显热。然而,在多大程度上避免显热形成首先是由水和TFVC的存在(不存在)介导的,目前尚不清楚。TFVC既介导陆地表面水的可用性,又驱动潜热产生的潜力(蒸散,ET)。虽然潜热与局部比全球降温/变暖更直接相关,它由光合作用和碳封存驱动,并为额外的云形成和云顶反射率提供动力,两者都推动了全球降温。TFVC损失减少了水的储存,沉淀回收,和顺风降雨潜力,从而推动ET(潜热)和云形成的减少。通过减少潜热,云的形成,和降水,因此,森林砍伐为变暖(显热形成)提供动力,这进一步减少了TFVC的生长(碳封存)。大规模的树木和森林恢复可以,因此,通过固碳和云形成的主要因果途径,对全球和地表温度冷却做出了重要贡献。
Scientific innovation is overturning conventional paradigms of forest, water, and energy cycle interactions. This has implications for our understanding of the principal causal pathways by which tree, forest, and vegetation cover (TFVC) influence local and global warming/cooling. Many identify surface albedo and carbon sequestration as the principal causal pathways by which TFVC affects global warming/cooling. Moving toward the outer latitudes, in particular, where snow cover is more important, surface albedo effects are perceived to overpower carbon sequestration. By raising surface albedo, deforestation is thus predicted to lead to surface cooling, while increasing forest cover is assumed to result in warming. Observational data, however, generally support the opposite conclusion, suggesting surface albedo is poorly understood. Most accept that surface temperatures are influenced by the interplay of surface albedo, incoming shortwave (SW) radiation, and the partitioning of the remaining, post-albedo, SW radiation into latent and sensible heat. However, the extent to which the avoidance of sensible heat formation is first and foremost mediated by the presence (absence) of water and TFVC is not well understood. TFVC both mediates the availability of water on the land surface and drives the potential for latent heat production (evapotranspiration, ET). While latent heat is more directly linked to local than global cooling/warming, it is driven by photosynthesis and carbon sequestration and powers additional cloud formation and top-of-cloud reflectivity, both of which drive global cooling. TFVC loss reduces water storage, precipitation recycling, and downwind rainfall potential, thus driving the reduction of both ET (latent heat) and cloud formation. By reducing latent heat, cloud formation, and precipitation, deforestation thus powers warming (sensible heat formation), which further diminishes TFVC growth (carbon sequestration). Large-scale tree and forest restoration could, therefore, contribute significantly to both global and surface temperature cooling through the principal causal pathways of carbon sequestration and cloud formation.