1. Tiada korelasi yang jelas dan berkadar langsung di antara pemanasan global dengan penipisan ozon (bersumber CFC).
2. Sejak diutuskan ‘surat untuk kemanusiaan’ pada tahun 1992 sehingga surat kedua pada tahun 2017, hanya kebimbangan berkaitan penipisan ozon yang telah diambil tindakan bersepadu; misalnya menerusi ratifikasi Protokol Montreal.
3. Pemasalahan berkaitan ozon hanyalah salah satu juzuk daripada kerisauan terhadap ekosistem atmosfera.
4. Surat pada tahun 1992 memberikan ‘amaran’ awal berkenaan hasil buat dan kerja tangan manusia yang akan merosakkan alam buana; dalam aspek atmosfera, air, lautan, tanah dan hidupan.
5. Dua surat tersebut telah diperaku dan ditandatangani oleh ribuan saintis termasuk tokoh ulung saintis global.
These and other insights led to the concept of planetary boundaries (PBs), which was first presented in an article in Nature in 2009 (Rockström et al. 2009a) followed by a longer version in Ecology & Society shortly after (Rockström et al. 2009b).
A team of 28 scientists convened by the Stockholm Resilience Centre and the Stockholm Environment Institute introduced the concept and proposed nine key PBs as a proof-of-concept.
Seven of these nine boundaries were quantified and specific boundary values were proposed. Figure 1 illustrates global performance on the nine PBs, where the green area represents the safe operating space defined by all the planetary boundaries. The yellow bars represent the most recent measurements available on each PB.
The initial review of global performance therefore suggests that humanity as a whole has transgressed three boundaries: climate change, rate of biodiversity loss and alteration of the nitrogen cycle
These and other insights led to the concept of planetary boundaries (PBs), which was first presented in an article in Nature in 2009 (Rockström et al. 2009a) followed by a longer version in Ecology & Society shortly after (Rockström et al. 2009b).
A team of 28 scientists convened by the Stockholm Resilience Centre and the Stockholm Environment Institute introduced the concept and proposed nine key PBs as a proof-of-concept.
Seven of these nine boundaries were quantified and specific boundary values were proposed. Figure 1 illustrates global performance on the nine PBs, where the green area represents the safe operating space defined by all the planetary boundaries. The yellow bars represent the most recent measurements available on each PB.
The initial review of global performance therefore suggests that humanity as a whole has transgressed three boundaries: climate change, rate of biodiversity loss and alteration of the nitrogen cycle
