Person:
McColl, Kaighin

Profile Picture

Email Address

AA Acceptance Date

Birth Date

Research Projects

Organizational Units

Job Title

Last Name

McColl

First Name

Kaighin

Name

McColl, Kaighin

Filters

2018 - 201912020 - 20211

Settings

Author's Publications: search.filters.isAuthorOfPublication.70223fd3-114a-4978-b60c-9d2ff1d5fa05

Search Results

Now showing 1 - 2 of 2
  • No Thumbnail Available
    Publication
    Moisture pulse-reserve in the soil-plant continuum observed across biomes
    (Springer Nature, 2018-12) Feldman, Andrew F.; Short Gianotti, Daniel J.; Konings, Alexandra G.; McColl, Kaighin; Akbar, Ruzbeh; Salvucci, Guido D.; Entekhabi, Dara
    The degree to which individual pulses of available water drive plant activity across diverse biomes and climates is not well understood. It has previously only been investigated in a few dryland locations. Here, plant water uptake following pulses of surface soil moisture, an indicator for the pulse–reserve hypothesis, is investigated across South America, Africa and Australia with satellite-based estimates of surface soil and canopy water content. Our findings show that this behaviour is widespread: occurring over half of the vegetated landscapes. We estimate spatially varying soil moisture thresholds at which plant water uptake ceases, noting dependence on soil texture and proximity to the wilting point. The soil type and biome-dependent soil moisture threshold and the plant soil water uptake patterns at the scale of Earth system models allow a unique opportunity to test and improve model parameterization of vegetation function under water limitation.
  • No Thumbnail Available
    Publication
    No projected global drylands expansion under greenhouse warming
    (Springer Science and Business Media LLC, 2021-03-11) Berg, Alexis; McColl, Kaighin
    Drylands, comprising land regions characterized by water-limited, sparse vegetation, have commonly been projected to expand globally under climate warming. Such projections, however, rely on an atmospheric proxy for drylands, the ‘aridity index’, which has recently been shown to yield qualitatively incorrect projections of various components of the terrestrial water cycle. Here, we use an alternative index of drylands, based directly on relevant ecohydrological variables, and compare projections of both indices in CMIP5 climate models as well as Dynamic Vegetation Models. The aridity index overestimates simulated ecohydrological index changes. This divergence reflects different index sensitivities to hydroclimate change and opposite responses to the physiological effect on vegetation of increasing atmospheric CO2. Atmospheric aridity is thus not an accurate proxy of future drylands extent. Despite greater uncertainties than in atmospheric projections, climate model ecohydrological projections indicate no global drylands expansion under greenhouse warming, contrary to previous claims based on atmospheric aridity.