Posted onJune 16, 2023|Comments Off on New evidence that polar bears survived 1,600 years of ice-free summers in the early Holocene
New evidence indicates that Arctic areas with the thickest ice today probably melted out every year during the summer for about 1,600 years during the early Holocene (ca. 11.3-9.7k years ago), making the Arctic virtually ice-free. As I argue in my new book, this means that polar bears and other Arctic species are capable of surviving extended periods with ice-free summers: otherwise, they would not be alive today.
Money quote:Here we show marine proxy evidence for the disappearance of perennial sea-ice in the southern Lincoln Sea during the Early Holocene, which suggests a widespread transition to seasonal sea-ice in the Arctic Ocean. [Detlef et al. 2023: Abstract]
Posted onMarch 13, 2022|Comments Off on Good news for polar bears and seals: new study finds multiyear Arctic sea ice is getting thinner
The fact that multiyear sea ice got thinner between 2018 and 2021 as documented by a new study, is ultimately good news for polar bears: less multiyear ice compared to first year ice is better for all marine mammals in the Arctic. Polar bears and seals, for example, are dependent on the seasonal ice that forms every winter (Atwood et al. 2016; Durner et al. 2009). Multiyear ice is simply too thick for any purpose except as a summer refuge for polar bears (for which land will do just as well) and a platform for maternity dens over the winter, for which thick first year ice will often do just as well (Anderson et al. 2012; Rode et al. 2018).
Posted onSeptember 24, 2020|Comments Off on Polar bear researchers try very hard to make good news in Kane Basin sound trivial
In an astonishing display of under-selling good news, the authors of a new paper announcing that Kane Basin polar bears are doing well have avoided mentioning that the population increased substantially since the 1990s and insist that any benefits will be short-lived.
Kane Basin population size at 2013 was 357 (range 221 – 493), up from 224 (range 145 – 303) in 1997. That’s an increase of 59% based on a 2016 recalculation of the 1997 population estimate of 164 (Crockford 2020) – it would have been a 118% increase otherwise.
Both the paper and the press release also claim, despite acknowledging that there is no evidence for this conclusion (“the duration of these benefits is unknown“), that this good news will probably not last because computer models say beneficial conditions might not persist beyond the end of the century.
As always, if you’d like to see this paper, use the ‘contact me’ page to request a copy (it’s paywalled).