Recently I identified a counterattack trying to defend the failed anthropogenic global warming (AGW) hypothesis. Claims about Arctic ice melt this summer (2012) are another example. Data and analysis are wrong, but they need to scare a disinterested public.
I know about arctic sea ice from flying ice and anti-submarine patrols on Canada’s east coat for four years then five years search and rescue in the Arctic. I later worked with members of the Canadian Polar Shelf Project and researchers producing Hudson Bay ice reconstructions.
Claims of declining ice conditions use satellite records that produced results after 1980. Mark Serreze, Director of the National Snow and Ice Data Center (NSIDC) publicly attacked “anti-science misinformers” and used this data to claim sea ice is at a record low of 4.1 million sq. km. Anthony Watts shows this was belied by another NSIDC “new and improved” measure of 4.7 million sq. km.
“In order to extend diagnoses of recent sea-ice variations beyond the past few decades, a century-scale digital dataset of Arctic sea-ice coverage has been compiled. For recent decades, the compilation utilizes satellite-derived hemispheric datasets. Regional datasets based primarily on ship reports and aerial reconnaissance are the primary inputs for the earlier part of the 20th century.”
These reconstructions have no value. As the Arctic Climate Impact Assessment (ACIA) said,
“The observational database for the Arctic is quite limited, with few long-term stations and a paucity of observations in general.”
If you can’t measure accurately with satellites, it’s impossible from the historic record.
NSIDC’s different results between models illustrate the problem. Other agencies get different estimates again. NOAA says the ice level is 5.1 million sq..km. while NATICE interactive maps show over 6.1 million sq..km (diagram).
The NATICE map illustrates the problem of determining ice extent. Notice there are no 100% ice areas. Prevailing Polar Easterlies drive the pack ice in a constant movement around the Pole creating wind driven open areas. Other large open areas include polynas. Satellites are fooled by meltwater on top of the ice and vast areas of broken and slush ice (yellow). How would you define ice and its limits in this Bering Straits satellite image?
For Arctic information the Intergovernmental Panel on Climate Change (IPCC) 2007 used the ACIA report. It said,
“Over the course of millions of years, the Arctic has experienced climatic conditions that have ranged from one extreme to another.”
Within the last 10,000 years several periods were warmer than today. Longest was the Holocene Optimum between 8000 and 5000 years ago (ya); the Minoan Warm Period 3400 ya; the Roman Warm Period 2400 ya; the Medieval Warm Period 1000 ya and most recently the 1930s warm period.
Temperature isn’t the main cause of current changes in Arctic ice. Wind pattern changes at the Polar Front (diagram) explain changing ice conditions that make ice extent more difficult to determine.
Rossby Waves along the Polar Front, have become more meridional with increased north/south winds. Many reports indicate the pattern.
“Arctic sea ice waxes and wanes throughout the year, and conditions fluctuate each season and year—including conditions in the Bering Sea. Although sea ice extent in mid-January 2012 was not at a record high, it was the highest ice extent in several years, according to the National Snow and Ice Data Center.”
A plot of Bering Sea ice in March shows the pattern and the record level in 2012. As one media outlet reported,
“The amount of floating ice in the Arctic’s Bering Sea – which had long been expected to retreat disastrously by climate-Cassandra organisations such as Greenpeace – reached all-time record high levels last month, according to US researchers monitoring the area using satellites.”
Here is the Meridional wind pattern in action.
“As winds from the north pushed Arctic ice southward through the Bering Strait, the ice locked together and formed a structurally continuous band known as an ice arch, which acts a bit like a keystone arch in a building.”
A 2011 Journal of Geophysical Research article explains,
“The perennial (September) Arctic sea ice cover exhibits large interannual variability, with changes of over a million square kilometers from one year to the next. Here we explore the role of changes in Arctic cyclone activity, and related factors, in driving these pronounced year-to-year changes in perennial sea ice cover.”
The same meridional pattern is occurring at the South Pole.
“It’s no secret that the South Pole in Antarctica is one of the coldest places on Earth. But this year it got really cold faster than ever, breaking a 30-year-old record for the earliest the temperature has dropped below minus 100 degrees Fahrenheit (minus 73.3 degrees Celsius).”
“The record comes less than four months after an altogether different mark was set at the South Pole during the austral summer. On Christmas Day, the temperature officially hit 9.9F (minus 12.3C) at about 3:50 p.m., to become the warmest day ever at the South Pole.”
“Just last September, another significant record fell when the peak wind speed was clocked at 58 miles per hour (mph), or 50 knots — the strongest ever at the South Pole.”
Ice conditions are changing; they always have and always will. Much warmer conditions occurred often in the recent past, but current changes are more due to changing wind patterns than temperature. Claims otherwise are political climate science trying to defend failed political climate science.