Scientists have been debating whether or not mantle plume heat contributes to western Antarctica’s instability. Some recent studies provided evidence this might be the case, but even this study’s authors were skeptical. “I thought it was crazy,” Hélène Seroussi, the study’s co-author and scientist at NASA’s Jet Propulsion Laboratory, said in a release. “I didn’t see how we could have that amount of heat and still have ice on top of it,” Seroussi said in a statement. NASA says Seroussi’s study provides more evidence of geothermal activity underneath a portion of the world’s largest ice sheet.
2. The Western Antarctic Peninsula has been rapidly cooling since 1999 (-0.47°C per decade), reversing the previous warming trend and leading to “a shift to surface mass gains of the peripheral glacier” (Oliva et al., 2017).
3. The Greenland ice sheet (GIS) has been melting so slowly and so negligibly in recent decades that the entire ice sheet’s total contribution to global sea level rise was a mere 0.39 of a centimeter (0.17 to 0.61 cm) between 1993 and 2010 (Leeson et al, 2017) . That’s a sea level rise contribution of about 0.23 mm/year since the 1990s, which is a canyon-sized divergence from the 61 mm/year that adherents of peer-reviewed, “consensus” climate science have projected for the coming decades.
And now Australian scientists have published a new paper in the journal Earth Systems and Environment that “does not support the notion of rapidly changing mass of ice in Greenland and Antarctica“. The paper highlights the “loud divergence between sea level reality” and “the climate models [that] predict an accelerated sea-level rise driven by the anthropogenic CO2 emission."
Global Sea Levels Actually Rising About 1 mm/yr… Not 3+ mm/yr -- McAneney et al., 2017: Global averaged sea-level rise is estimated at about 1.7 ± 0.2 mm year−1 (Rhein et al. 2013), however, this global average rise ignores any local land movements. Church et al. (2006) and J. A. Church (2016; personal communication) suggest a long-term average rate of relative (ocean relative to land) sea-level rise of ∼1.3 mm year. …
In newly published papers, scientists have reported that Arctic sea ice extent grew during the decades from the 1940s to the 1980s before declining after the 1980s. The Arctic sea ice trend has thus undergone an oscillation rather than a linear recession, contradicting the models.
Furthermore, the instrumental record indicates that Arctic temperatures have stopped rising since about 2005.
On the other side of the planet, the sea ice surrounding Antarctica has been growing since the 1970s, or for nearly 40 years now. This sea ice expansion coincides with an overall Southern Ocean cooling trend of about -0.3°C per decade since 1979.
No Net Arctic Warming Trend Since The 1930s, 1940s
"In 2017 about 33% of the March maximum was retained, so the melt season losses were considerably less than in the past."
"Earlier observations showed that Arctic ice extents were low in the 1940s, grew thereafter up to a peak in 1977, before declining. That decline was gentle until 1994 which started a decade of multi-year ice loss through the Fram Strait. There was also a major earthquake under the north pole in that period. In any case, the effects and the decline ceased in 2007, 30 years after the previous peak. Now we have a plateau in ice extents, which could be the precursor of a growing phase of the quasi-60 year Arctic ice oscillation."