Search results for "Climate system"
showing 3 items of 3 documents
Weakening of annual temperature cycle over the Tibetan Plateau since the 1870s
2017
The annual cycle of extra-tropical surface air temperature is an important component of the Earth's climate system. Over the past decades, a reduced amplitude of this mode has been observed in some regions. Although attributed to anthropogenic forcing, it remains unclear when dampening of the annual cycle started. Here we use a residual series of tree-ring width and maximum latewood density from the Tibetan Plateau >4,000 m asl to reconstruct changes in temperature seasonality over the past three centuries. The new proxy evidence suggests that the onset of a decrease in summer-to-winter temperature difference over the Tibetan Plateau occurred in the 1870s. Our results imply that the influen…
Recognition and Support of ICCAs in Italy
2012
The concept of ICCA was introduced and first discussed in Italy during two workshops held in 2004 and 2005. The notion very well fits the tradition domestically known in terms of common properties (CPs) and ‘civic uses’ lands (proprietà colletive e demani civici), a category referring to lands and the natural resources used in common by a community. They include a diversity of governance solutions derived from their different historical recognition. CPs and civic uses lands in Italy achieved recognition under agricultural law and were particularly associated to the agro-forestry and pastoral sector. They have been subject to regulations of restrictions on change of land use and protected by…
Spectral biases in tree-ring climate proxies
2013
Seamless quantification of past and present climate variability is needed to understand the Earth’s climate well enough to make accurate predictions for the future. This study addresses whether tree-ring-dominated proxy data properly represent the frequency spectrum of true climate variability. The results challenge the validity of detection and attribution investigations based on these data. External forcing and internal dynamics result in climate system variability ranging from sub-daily weather to multi-centennial trends and beyond1,2. State-of-the-art palaeoclimatic methods routinely use hydroclimatic proxies to reconstruct temperature (for example, refs 3, 4), possibly blurring differe…