Showing posts from May, 2016

How Much Warming Have Humans Caused?

How much did temperatures rise since 1900? Differences in baseline (reference period) can result in dramatic differences in temperature rise. The U.K. Met Office HadCRUT4 dataset typically presents temperature anomalies relative to a 1961-1990 baseline. NASA typically uses a 1951-1980 baseline, but the NASA website allows for different baselines to be selected. When selecting a 1961-1990 baseline, the temperature of the past period of six months was 1.05°C (1.89°F) higher than this baseline, as illustrated by the NASA map in the left panel of the image below. But when compared to 1890-1910, the temperature of the past period of six months was 1.48°C (or 2.664°F) higher, as illustrated by the NASA map in the right panel of the image below. A polynomial trend can reduce variability such as caused by volcanoes and El Niño events. The graph below was created with the NASA L-OTI monthly mean global surface temperature anomaly, which has a 1951-1980 baseline, and then with 0.29°C added, whic

Arctic Climate Records Melting

An intensely warm winter and spring are melting climate records across Alaska, reports NOAA in the post ' Arctic set for record-breaking melt '. The January-April 2016 period was 11.4°F (6.4°C) warmer than the 20th century average, reports NOAA . The NOAA image below further illustrates the situation. The sea ice is melting rapidly. Warm water from the Mackenzie River contributes to dramatic melting in the Beaufort Sea, as illustrated by the image below, showing that on May 20, 2016, the Arctic Ocean was 5°F (2.8°C) warmer than in 1981-2011 at the delta of the Mackenzie River. The image below shows that on May 20, 2016, sea ice extent was 10.99 million square km, compared to the 12.05 million square km extent of the sea ice in May 20, 2012, as measured by JAXA .  Sea ice reached a record minimum extent of 3.18 million square km on September 15, 2012, and chances are that the sea ice will be largely gone by September 2016. The year 2016 is an El Niño year and insolation during

Further Confirmation Of Arctic Sea Ice Dramatic Fall

Since early April, 2016, there have been problems with the sensor on the F-17 satellite that provided the data for many Arctic sea ice images. On April 12, NSIDC issued a notice that it had suspended the provision of sea ice updates. On May 6, NSIDC announced that it had completed the  shift to another satellite . The red dotted line in the image below shows data from the F-18 satellite from April 1 to May 15, 2016. The JAXA site also provides sea ice extent images, obtaining data from a Japanese satellite. They show that Arctic sea ice extent on May 15, 2016 was 11,262,361 square km, 1.11 million square km less than it was on May 15, 2012. The Cryosphere Today is still using data from the F17 satellite, showing some weird spikes. Albert Kallio has taken a recent image and removed faulty spikes, resulting in the image below showing sea ice area up to May 3, 2016. [ yellow line is 2016, red line is 2015 ] Importantly, above image confirms that Arctic sea ice in 2016 has indeed been ve

Arctic Sea Ice gone by September 2016?

Arctic sea ice extent is very low, much lower than it was in other years at this time of year. On May 11, 2016, Arctic sea ice extent was 12.328 million square km, according to the National Snow and Ice Data Center ( NSIDC ), while JAXA 's figure for extent on May 11, 2016, was only 11.57 million square km. [ based in image from JAXA  ] JAXA figures show that Arctic sea ice extent on May 9, 2016, was 11.68 million square km, more than 18 days ahead on 2012 and 1.1 million square km smaller than it was on May 9, 2012. The image on the right compares the Beaufort Sea and the northern part of Alaska between May 9, 2012 and May 9, 2016. As the image illustrates, there now is a lot less ice and snow cover than there was on 2012. The situation looks set to deteriorate further over the coming months. The image below shows temperature forecast to reach anomalies as high as 5.19°C or 9.34°F for the Arctic as a whole (forecast for May 19, 2016, 0300 UTC), with temperature anomalies at the t

Wildfire Danger Increasing

Wildfires are starting to break out in British Columbia, Canada. The wildfire on the image below started on May 1, 2016 (hat tip to Hubert Bułgajewski‎ ). The coordinates of the wildfire are in the bottom left corner of above map. They show a location where, on May 3, 2016, it was 26.0°C (or 78.8°F). At a nearby location , it was 27.6°C (or 81.8°F) on May 3, 2016. Both locations are indicated on the map on the right. These locations are on the path followed by the Mackenzie River, which ends up in the Arctic Ocean. Wildfires aggravate heat waves as they blacken the soil with soot. As the Mackenzie River heats up, it will bring warmer water into the Arctic Ocean where this will speed up melting of the sea ice. Moreover, winds can carry soot high up into the Arctic, where it can settle on the sea ice and darken the surface, which will make that more sunlight gets absorbed, rather than reflected back into space as before. The danger of wildfires increases as temperatures rise. The image