For a generation, governments around the world have been committed to sustainable development as a policy goal. This has been supported by an array of new policies ranging from international agreements, to national strategies, environmental laws at many levels of government, regional programs, and local plans. Despite these efforts, decades of scientific monitoring indicate that the world is no closer to environmental sustainability and in many respects the situation is getting worse. This paper argues that a significant contributing factor to this situation is policy implementation failure. A systematic review of the literature reveals that the failure to achieve the intended outcomes of environmental policies is due to economic, political and communication factors. Conflict between the objectives of environmental policies and those focused on economic development, a lack of incentives to implement environmental policies, and a failure to communicate objectives to key stakeholders are all key factors that contribute to the inability to attain environmental sustainability.

Stories belonging to Australian Aboriginal groups tell of a time when the former coastline of mainland Australia was inundated by rising sea level. Stories are presented from 21 locations from every part of this coastline. In most instances it is plausible to assume that these stories refer to events that occurred more than about 7000 years ago, the approximate time at which the sea level reached its present level around Australia. They therefore provide empirical corroboration of postglacial sea-level rise. For each of the 21 locations, the minimum water depth (below the present sea level) needed for the details of the particular group of local-area stories to be true is calculated. This is then compared with the sea-level envelope for Australia (Lewis et al., Quaternary Science Reviews 74, 2013), and maximum and minimum ages for the most recent time that these details could have been observed are calculated. This method of dating Aboriginal stories shows that they appear to have endured since 7250–13 070 cal years bp (5300–11 120 bc). The implications of this extraordinary longevity of oral traditions are discussed, including those aspects of Aboriginal culture that ensured effective transgenerational communication and the possibility that traditions of comparable antiquity may exist in similar cultures.

In his News and Analysis piece reporting on the newly released fifth assessment report (AR5) by Working Group I (WGI) of the Intergovernmental Panel on Climate Change (IPCC) (“A Stronger IPCC Report,” 4 October, p. [23][1]), R. A. Kerr highlights three fundamental conclusions about climate change that were assessed with equal or greater confidence than in previous IPCC reports. He also points to three “contentious points” on which he states that the AR5 “took a moderate line.” Kerr includes sea-level projections among these points, and reports “a rise of 40 to 60 centimeters by late in the century and a worst case of 1 meter by 2100, [which is] higher than in 2007 but far below the meter or two of sea-level rise that some expect.” As the authors of the IPCC WGI AR5 chapter on “Sea-Level Change,” we wish to clarify that for the highest emission scenario considered (RCP8.5), the AR5 reported a “likely” range of 0.45 to 0.82 m for sea-level projections for the late 21st century (average over 2081 to 2100) and of 0.52 to 0.98 m by 2100. The difference in sea level between these two periods is large because in 2081 to 2100, the “likely” rate of rise is 8 to 16 mm per year, which is up to about 10 times the average rate of rise during the 20th century. In the calibrated uncertainty language of the IPCC, this assessed likelihood means that there is roughly a one-third probability that sea-level rise by 2100 may lie outside the “likely” range. That is, the AR5 did not exclude the possibility of higher sea levels. However, we concluded that sea levels substantially higher than the “likely” range would only occur in the 21st century if the sections of the Antarctic ice sheet that have bases below sea level were to collapse. We determined with medium confidence that “this additional contribution would not exceed several 10ths of a meter of sea-level rise during the 21st century.” We could not define this possible contribution more precisely because “there is currently insufficient evidence to evaluate the probability of specific levels above the assessed ‘likely’ range.” The upper boundary of the AR5 “likely” range should not be misconstrued as a worst-case upper limit, as was done in Kerr's story as well as elsewhere in the media and blogosphere. For policy and planning purposes, it may be necessary to adopt particular numbers as an upper limit, but according to our assessment, the current state of scientific knowledge cannot give a precise guide. ![Figure][2] CREDIT: ANDREW MANDEMAKER/WIKIMEDIA COMMONS [1]: /lookup/doi/10.1126/science.342.6154.23-b [2]: pending:yes