9. The restoration of biotic pump effects to restore rainfalls, rehydration and cooling (Walter Jehne)
The formation of the persistent enhanced humid hazes, their dual warming effects and the exponential increase in infrared heat being re-radiated from bare dry degraded lands exposed to solar radiation can all contribute to the creation of high-pressure heat domes over such regions.
These high-pressure heat domes invariably block the inflow of cooler moist air from marine or better-watered regions that potentially could bring in some precipitation nuclei and rain. As such our degradation, aridification and desertification of prior moist regions can become self-reinforcing.
Conversely, the induction of rain in dry landscapes can aid plant growth, transpiration and surface cooling to create low-pressure corridors and zones that can aid the inflow of such moist low-pressure air and rain to help rehydrate and re-green these regions relative to nearby, similar arid areas.
This biotic pump, humid air inflow effects, and zones may be seasonal or permanent and able to be induced via land management practices that optimize the regeneration of the soil carbon sponge, its water, infiltration, retention and thus the longevity of green growth and cooling in that zone.
Vast seasonal inflows of moisture from the oceans, such as in the Amazon and in different monsoons are influenced by these biotic pump effects and the aridity and management of the landscapes they flow over. As climates aridify and become less reliable and extreme, we should not take such humid air inflows at either a local or continental scale for granted. Instead we must regenerate and manage landscapes to optimize the effectiveness and reliability of such critical hydrological inputs.
More on sky rivers
Figure one: A roughly 8,000-kilometer-long atmospheric river extending from Asia to the Pacific Northwest was imaged by the Suomi NPP satellite on Oct. 14, 2017. Many interconnected factors influence where atmospheric rivers make landfall and how much precipitation they deliver. Credit: NASA Earth Observatory image by Joshua Stevens. (Image from the Earth Magazine website)