Up サバク化進行の現況 作成: 2024-03-26
更新: 2024-03-26

    現在進行のサバク化は，地質学的時間オーダーの地球史の，一大トピックである。
    ひとはいま，この一大トピックに遭遇している。
    しかし，「CO2排出地球温暖化」の目くらましに騙されて，この遭遇に気づいていない。

環境省 "The Global Desertification - The Situation, and the Challenges for Japan" から引用：


「地球の陸地の 41.3％ が，サバク化域」(2000年時点)


「世界人口の 34.7％ が，サバク化域に棲む」(2000年時点)


    Dryland subtypes are determined by the aridity index
      AI = P (annual precipitation) / PET (potential evapotranspiration)

    Dryland Subtype Aridity Index Characteristics
    Hyper-arid
    environments    		 AI＜0.05 There is no seasonal rainfall regime, and these areas offer very limited opportunities for human activity（Desert area）.
    Arid areas 0.05≦AI＜0.20 Annual precipitation values up to about 200 mm in winter rainfall areas and 300 mm in summer rainfall areas.
    Interannual rainfall variability is in the 50-100% range.
    Semiarid areas 0.20≦AI＜0.50 There are highly seasonal rainfall regimes and annual precipitation values up to 500 mm in winter rainfall areas and 800 mm in summer rainfall areas.
    Interannual rainfall variability is nonetheless high in the 25-50% range.
    Dry subhumid
    areas    		 0.50≦AI＜0.65 Less than 25% interannual rainfall variability and rain-fed agriculture is widely practiced