Antarctic precipitation and climate change predictions: Horizontal resolution and margin vs plateau issues

first_imgAll climate models participating in the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, as made available by the Program for Climate Model Diagnosis and Intercomparison (PCMDI) as the Coupled Model Intercomparison Project 3 (CMIP3) archive, predict a significant surface warming of Antarctica by the end of the 21st century under a moderate (SRESA1B) greenhouse-gas scenario. All models but one predict a concurrent precipitation increase but with a large scatter of results. The models with finer horizontal resolution tend to predict a larger precipitation increase. Because modeled Antarctic surface mass balance is known to be sensitive to horizontal resolution, extrapolating predictions from the different models with respect to model resolution mayprovide simple yet better multi-model estimates of Antarctic precipitation change than mere averaging or even more complex approaches. Using such extrapolation, a conservative estimate of the predicted precipitation increase at the end of the 21st century is +30 kgm–2 a–1 on the grounded ice sheet, corresponding to a >1mma–1 sea-level rise. About three-quarters of this rise originates from the marginal regions of the Antarctic ice sheet with surface elevation below 2250 m. This is where field programs are most urgently needed to better understand and monitor accumulation at the surface of Antarctica, and to improve and verify prediction models.last_img read more

Read More

Industry veteran Ambachtsheer criticises Dutch pensions system

first_imgDutch pension funds should split their portfolios into two separate segments and abandon the notion of intergenerational risk-sharing, Keith Ambachtsheer has argued.The director of the Rotman International Centre for Pension Management told IPE the risk-sharing element of the Dutch system was problematic, as it would always end with “the people with the power deciding things in their own interest”.He echoed previous comments that the current system was akin to US Nobel laureate John Nash’s game theory.“You can’t enforce [risk-sharing] unless you have a very strong governmental-type oversight that’s multi-generational, which is a pretty tough assumption,” he said. “Where the Dutch need to go is – rather than have a collective thing – simply divide their asset pool into a compounding component and a payment-certainty component,” the Toronto-based academic continued, noting that the two asset pools should not be mixed, as is currently the case in the Dutch system.He said he would keep “hammering away” at the idea until the Dutch “finally get it”.Ambachtsheer has previously expressed concern that a new concept of solidarity, whereby money is taken from pensions in payment, is changing the Dutch approach to pensions saving.Speaking at an event organised by the UK’s National Association of Pension Funds last year, he referenced Nash’s theory.“If you want a win-win game between various parties, you have to figure out how to keep it win-win,” he said. “If there’s a chance the game becomes win-lose, it will. And then it breaks down.”He has also been critical of previous proposals to revise the Dutch financial assessment framework (FTK) by allowing for a ‘nominal’ and a ‘real’ system of pension payments, deeming it flawed.For more on the FTK, including alternative proposals, see the March issue of IPElast_img read more

Read More

PHOTO: Brance Diversified Busy at Amelia Island

first_imgImage source: Brance DiversifiedBrance Diversified, Inc., a dredging and marine construction company servicing the state of Florida and surrounding areas, is currently conducting dredging operations in Amelia Island on Creekside Drive.So far, the Jacksonville based dredging contractor removed approximately 42,000 cubic yards of material from the Amelia Island Marina. The clean-up work at this site is underway at the moment, said Jennifer Mitchell from Brance Diversified.“We are also currently wrapping up some dredging work at the Vilano Boat Ramp in St. Augustine,” added Mitchell.Brance Diversified has just released this amazing photo from the Amelia Island dredging scheme.[mappress mapid=”24542″]last_img

Read More