knocker

A quick science lesson for Lord Lawson

The memorable winter of 2014 continues over the Eastern U.S., where an intensifying Winter Storm Pax has dumped up to a foot and a half of snow. Snowfall rates of 3" per hour have been observed in North Carolina, Pennsylvania, and New York this morning. A band of super-heavy snow set up over northern New Jersey, with some reports of 3 - 4" of snow falling in just 30 minutes. As of 9 am EST, over a foot of snow (12.3") was observed at the Baltimore Airport, 7" at New York City's Central Park, and 11" in Washington D.C. at American University. The 8.8" of snow so far today in Philadelphia makes the winter of 2013 - 2014 the 5th snowiest on record there, and the first time since record keeping began in 1884 that Philadelphia has had four separate six inch or greater snowstorms in a winter. From the 10 am EST Thursday NWS storm report, here are the top snowfall totals from Pax: http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2631

Yesterdays storm stats. http://metofficenews.wordpress.com/2014/02/13/12-february-2014-storm-statistics/

Yes it rather depends where you are. As I've already mentioned the METO have the fronts through Camborne between 0900-1200. Guess who has a doctors appointment at 0945?

Abrupt Climate Change Focus of New Yale Forum Video An issue that for years received only passing attention, even in many professional circles, abrupt climate change and potential impacts on at-risk ecosystems is getting more attention in the scientific sphere. Senior Scientists discuss the potential for sudden disruptions of human and natural systems as a consequence of climate change

Indeed it is John. I posted it in the climate area a couple of days ago and printed it to digest which I'm still doing. Your other point I'm afraid is wishful thinking.

The Worst of the Winter Weather Is Over. Here's What's Left to Come. http://www.slate.com/blogs/future_tense/2014/02/12/pax_winter_storm_brings_ice_snow_chaos_to_the_south.html

And perhaps before that. http://forum.netweather.tv/topic/64228-when-the-monsoon-failed/

Incredible that nobody can be bothered to read the link that Bobby posted and then if they wish post some scientific comment. I thought I was in the sceptic thread for a minute. I'll post the relevant section without the diagrams. I've highlighted the relevant piece regarding Indonesia. Global Context of recent UK Weather The exceptional weather experienced over the UK in December and January was part of a hemispheric pattern of severe weather. This included exceptionally low temperatures across Canada and the US from the mid-west to the eastern seaboard and reaching as far south as Texas (Figure 12). The peak of this cold event occurred on the 5th and 6th January, coinciding with the storminess over the UK. Early estimates suggest that in the US alone over 200 million people were affected with costs in excess of $5bn. These extreme weather events on both sides of the Atlantic were embedded in a persistent pattern of perturbations to the upper tropospheric jet stream2 (Figure 13). The climatological distribution of the winter jet streams (Figure 13, left panels) shows the well-known Asian-Pacific jet stream, which extends across North Africa and out into the North West Pacific, close to Japan. A second jet stream forms over the US, extending in a north-easterly direction across the North Atlantic towards the UK. The North Atlantic jet stream acts to steer weather systems towards the UK, but there also exists a symbiotic relationship between the jet stream and the depressions that form on its flanks. The jet stream provides the atmospheric conditions that are favourable for cyclogenesis (the formation of depressions), but it also depends on the momentum from the depressions to maintain its own strength. So it is possible on occasions to observe a strengthening of the jet stream when there is a particularly active sequence of depressions, as was the case in December 2013 and January 2014 (Figure 13, right panels). During December and January 2013/14 the pattern of winds over the North East Pacific and North America was very disturbed (Figure 13, right panels). The North Pacific jet was deflected a long way north, with a secondary branch extending southwards into the tropical Pacific accentuating the separation of the Pacific and Atlantic jet streams. The effects of this over North America and into the North Atlantic were profound. The deflection of the jet to the north led to colder air being carried south over Canada and the northern US (as seen in Figure 13) to enter the North Atlantic jet and establish a stronger than normal temperature gradient at the entrance of the North Atlantic Jet. This acted to strengthen the jet and provide the conditions for active cyclogenesis, which in turn led to a sequence of strong storms across the UK throughout December and January. As Figure 13 indicates, the North Atlantic jet was, on average, as much as 30% stronger than normal. Similar, but weaker, conditions can be seen in the southern hemisphere, mirroring those to the north and supporting the view that the tropics were driving at least some of what has been experienced this winter. In the lower troposphere, at 850mb (Figure 14), the winds over the North Atlantic were much stronger than normal during December and January 2013/14. Likewise the perturbed flow over the North Pacific is also very clear with an anomalous anticyclonic system off the west coast of North America, which has been a persistent feature of this winter’s weather. At these lower levels in the atmosphere, the clash between the cold northerly airstream from North America with the warm, moist airstream from the tropical Atlantic is notable (see circled areas on Figure 14). Not only would this act to invigorate storms forming on the jet stream, but the inflow of warm, moist air from the tropics would enhance the moisture being carried by the storm systems and potentially lead to higher rainfall downstream over the UK. It is clear from Figures 13 and 14 that there is a strong association between the stormy weather experienced in the UK during December and January 2013/14 and the up-stream perturbations to the jet stream over North America and the North Pacific. So what might be the drivers of the changes over the Pacific? It is well understood that El Nino and its cold counterpart La Nina have major effects on weather patterns around the globe3. Indeed the changes in the jet stream over the North Pacific, described above, are typical of what is observed during La Nina events (Figure 15), with the jet being deflected to the north by anomalously high pressure off the western seaboard of the US, and with a variable jet to the south along which disturbed weather forms. The polar jet stream is then deflected a long way south over the US bringing cold air with it before re-joining the southern branch of the Pacific jet stream at the start of the North Atlantic jet stream, essentially as described in Figure 13 for December and January 2013/14. It is reasonable therefore to argue that the weather that the UK has experienced has its roots in the tropics. However, the current sea surface temperature anomalies (Figure 16, left panel) suggest that neither El Nino nor La Nina were active, with temperatures in the equatorial East Pacific Ocean being close to normal. The West Pacific remains anomalously warm, as it has done for much of the past decade. Elsewhere in the Pacific the patterns of sea surface temperature anomalies still display elements of the negative phase of the Pacific Decadal Oscillation (PDO) that has contributed to the recent pause in global surface warming4. Likewise the very warm waters in the North Pacific (Figure 16) are a result of the systematic weakening of the Aleutian Low during the last decade, driven by the negative phase of the PDO. In the North Atlantic, ocean temperatures continue to be above normal near 300N which would also contribute to a strengthened north-south temperature gradient across the storm track, aiding the development of storms. As Figure 16 shows, the sub-tropical Atlantic is currently warmer than the average for the last 30 years (1981-2010), but substantially warmer than it was 30 years prior to that (1951-1980). This in itself will potentially increase the moisture being held in the atmosphere, above the ocean, and entering the storm systems as they moved towards the UK. In terms of the global influences of El Nino/La Nina, it is the changes in tropical rainfall patterns that ultimately drive the perturbations to the atmospheric circulation described by Figure 15. So whilst the sea surface temperatures suggest neutral conditions in the tropical East Pacific, it seems that tropical rainfall patterns in December and January are consistent with a La Nina signal, with higher than normal rainfall over the West Pacific, Indonesia and the eastern Indian Ocean throughout December and January (Figure 17). Bearing in mind that the average rainfall in this region is between 8 and 12 mm/day, these anomalies in rainfall are substantial. This distribution of rainfall across the tropical Pacific is consistent with the warmer than normal sea surface temperatures in the tropical West Pacific (Figure 16, left panel). As well as the above normal rainfall over Indonesia, Figure 17 also highlights the sequence of disturbances entering the tropical East Pacific as part of the southern branch of the Pacific jet stream described by Figure 15 and evident in Figure 13. Even in these monthly mean fields it is possible to see the continuity between the disturbed weather over the tropical East Pacific and the run of depressions that brought heavy rain to the UK throughout the winter. Taking all the evidence from the winds and the rainfall, a notable feature of this winter’s storms is the unusual reach of the North Atlantic jet stream back into the East Pacific and the continuous feed of disturbances from the tropical Pacific into the storm track. The disturbances in the tropical East Pacific come, themselves, from the North Pacific, and are able to propagate into the tropics because of the westerly winds in the upper troposphere over the East Pacific (Figure 13); they themselves are part of the response of the winds to the enhanced rainfall over Indonesia. Known as the westerly duct, this is an important conduit through which the tropics and extratropics are able to interact5; in La Nina-like conditions, as experienced this winter, the duct is stronger than normal and the propagation of disturbances from the North Pacific more significant. As is evident in Figure 13, the ‘buckling’ of the jet stream over the Pacific and North America became much more pronounced during January 2014, as the precipitation anomaly over Indonesia and the West Pacific strengthened (Figure 17). A notable feature of this anomalous area of tropical precipitation is its northwards extent into the winter hemisphere where it is able to interact with the North Pacific jet and generate Rossby waves6 that propagate along the jet and act to reinforce the huge meander of the jet stream off the west coast of North America. At the same time, Rossby waves propagate along the southern branch of the jet stream and enter the tropical East Pacific through the westerly duct, creating weather disturbances that can then get caught up in the entrance region of the Atlantic jet stream. These Rossby wave interactions are very complex but appear to be fundamental to understanding this winter’s weather. The influence of the Pacific is very clear in the days preceding the major storm of 5/6th January. Figure 18 contains a sequence of maps from 31st December to 5th January showing satellite infrared observations of cloudiness on the left and 250mb winds on the right. The wave disturbances entering the tropical East Pacific westerly duct can be clearly seen in the wind fields throughout the period. These waves move into the entrance region of the North Atlantic jet which reaches unusually far west into the tropical Pacific. At the same time it is evident that waves are also entering the North Atlantic jet from the north via the polar jet. The sequence of satellite imagery of cloudiness shows how these waves translate into the development of the major cyclone over the North Atlantic by 5th January. What Figure 18 also demonstrates very nicely is that the jet stream is highly variable day by day. It acts as a guide along which the Rossby waves propagate and is also strongly influenced by those waves. Early in the sequence shown in Figure 18 the jet stream over the North Atlantic is strong but as the major storm develops on 4th and 5th January the jet stream weakens as the storm takes momentum from it. Understanding these complex interactions between atmospheric waves and the jet stream is at the heart of understanding and forecasting our weather.

It's been pretty grotty day here with frequent heavy rain showers. Tomorrow of course is going to be worse with the fronts through between 0900-1200 and then the wind veering SW and strengthening gusting 65mph with heavy or moderate rain throughout.

Snow begins to pile up in South Jersey, North Jersey faces brunt during commute http://www.nj.com/news/index.ssf/2014/02/snow_begins_to_pile_up_in_south_jersey_north_jersey_faces_brunt_during_commute.html#incart_m-rpt-1

Two photos of Engine shaft at Barncoose Mine. The above ground photo is the capped shaft in the garden of what used to be the count house of the mine. The lady who lives there said they had been there for forty years and originally it was open but being afraid their kids would disappear they had it privately capped. The underground photo is the rising main of the shaft. Credit photo to Sharon Schwartz. Sharon is an expert on Cornish mining and has written extensively on it.

http://www.theregister.co.uk/2014/02/13/fusion_lawrence_livermore/ http://www.nature.com/nature/journal/vaop/ncurrent/full/nature13008.html

I felt the need to brighten up the morning so a quick glance at you know where. Anthony is in "It's the Sun again", mode. Quote of the day. If you have ever studied how the magnetic dynamo of the sun is so incredibly full of entropy, yet has cycles And back in 2008, he wrote: Some say it is no coincidence that 2008 has seen a drop in global temperature as indicated by several respected temperature indexes compared to 2007, and that our sun is also quiet and still not kick starting its internal magentic dynamo. http://blog.hotwhopper.com/2014/02/oh-no-not-its-sun-again-recycling.html

Live Winter Storm Blog: Traffic Chaos May Turn Raleigh and Charlotte Into This Storm’s Atlanta http://www.slate.com/blogs/future_tense/2014/02/12/pax_winter_storm_brings_ice_snow_chaos_to_the_south.html

A new NASA video of NOAA's GOES satellite imagery shows three days of movement of the massive winter storm that stretches from the southern U.S. to the northeast. Visible and infrared imagery from NOAA's GOES-East or GOES-13 satellite from Feb. 10 at 1815 UTC/1:15 p.m. EST to Feb. 12 to 1845 UTC/1:45 p.m. EST were compiled into a video made by NASA/NOAA's GOES Project at NASA's Goddard Space Flight Center in Greenbelt, Md. In the video, viewers can see the development and movement of the clouds associated with the progression of the frontal system and related low pressure areas that make up the massive storm. The video also shows the snow covered ground over the Great Lakes region and Ohio Valley that stretches to northern New England. The clouds and fallen snow data from NOAA's GOES-East satellite were overlaid on a true-color image of land and ocean created by data from the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA's Aqua and Terra satellites. http://www.nasa.gov/content/goddard/satellite-video-shows-movement-of-major-us-winter-storm/#.UvvvLs6cSpA

Just some more that has already been posted on and related matters. Heat stored in the western Pacific Ocean caused by an unprecedented strengthening of the equatorial trade winds appears to be largely responsible for the hiatus in surface warming observed over the past 13 years.New research published in the journal Nature Climate Change indicates that the dramatic acceleration in winds has invigorated the circulation of the Pacific Ocean, causing more heat to be taken out of the atmosphere and transferred into the subsurface ocean, while bringing cooler waters to the surface."Scientists have long suspected that extra ocean heat uptake has slowed the rise of global average temperatures, but the mechanism behind the hiatus remained unclear" said Professor Matthew England, lead author of the study and a Chief Investigator at the ARC Centre of Excellence for Climate System Science."But the heat uptake is by no means permanent: when the trade wind strength returns to normal - as it inevitably will - our research suggests heat will quickly accumulate in the atmosphere. So global temperatures look set to rise rapidly out of the hiatus, returning to the levels projected within as little as a decade."Earth imagery courtesy of NASA http://climatecrocks.com/2014/02/12/faux-pause-part-2/

A historic Southeast U.S. winter storm is pounding Georgia and South Carolina with heavy snow and thick coatings of freezing rain. Car crashes on icy roads from the storm have already killed six people--four in Texas, and two in Mississippi--and travel will be extremely dangerous over much of the South on Wednesday. As of 9 am EST on Wednesday, freezing rain amounts as high as 1/2" had already been observed in Central South Carolina near Columbia. Freezing rain rates as high as 0.1" per hour are expected along a swath from Atlanta, Georgia to the northeast coast of South Carolina. Over 1" of ice may accumulate from freezing rain in areas near Augusta, Georgia. Strong winds will combine with the freezing rain to blow down trees and power lines, and the Sperry-Piltz Ice Accumulation Index rates the potential impacts from areas which receive at least 3/4" of ice accompanied by winds in excess of 15 mph at a 4 on a scale of 1 to 5. At this level, expect "prolonged and widespread utility interruptions with extensive damage to main distribution feeder lines and some high voltage transmission lines/structures. Outages lasting 5 - 10 days." As of 9:45 am EST, 78,000 customers in Georgia had lost power, and power outages were increasing at a rate of 30,000 customers per hour. About 30,000 customers had lost power in South Carolina. http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=2630

"Believe it or not, the forecast for the Deep South’s impending icy apocalypse just got worse." My latest thoughts Today’s the Day Atlanta Could Lose a Quarter of Its Trees Eric Holthaus As the first pellets of sleet began pattering against windows in Georgia, new data were gathered overnight during a rare wintertime mission by Air Force Hurricane Hunter aircraft. Much as is typically done in a landfalling major hurricane, these data were fed into early morning weather computer models, in an impromptu experiment to increase forecast accuracy just hours before the storm struck. The results aren’t pretty. Anticipated ice totals have been bumped up significantly from yesterday’s already dire forecast. Here’s what the forecast looks like now in Georgia, where the biggest impacts are anticipated: http://www.slate.com/blogs/future_tense/2014/02/12/winter_storm_pax_deep_south_facing_crippling_category_5_ice_storm.html

MSLP with earth wind http://earth.nullschool.net/#current/wind/surface/level/overlay=mean_sea_level_pressure/orthographic=-0.78,47.10,1039

Great Modis HR Sat. at 1145. Just see Cornwall poking out in the clear. The image is credited to us "NERC Satellite Receiving Station, Dundee University, Scotland" http://www.sat.dundee.ac.uk/

Climate variability is larger on smaller spatial scales | Comparing global & Central England temperature since 1850

Expert reaction to continued flooding http://www.sciencemediacentre.org/expert-reaction-to-continued-flooding/

Reading this report it seems to me the critical research in the future is going to be centred around the dynamics of the jet stream. This does appear to be relatively poorly understood at the moment. The relevant part of the report. In seeking to answer questions about the impact of climate change on severe weather, there are two distinct steps to be taken. The first is to detect a change in either the frequency or intensity of storminess or rainfall events that is more than just the natural variability in UK weather. UK weather is notoriously volatile and so detection is particularly challenging. Severe storms have always affected the UK and are documented in many historical records. The intensity of recent storms is unusual, as the climatological records discussed earlier indicate, but not necessarily unprecedented. A comprehensive study of trends in storminess, for the period 1871-2010 from an ensemble of reanalyses by Wang et al. (2013)12 provides some important insights. They show a robust signal of increasing numbers of strong winter cyclones and with increasing intensity for the high latitude North Atlantic (Figure 21), covering the region to the north of the UK and including Iceland. This is associated with a reduction in storminess further south and supports a wide body of evidence for a poleward shift of the Atlantic storm track. However, their analysis of changes in storminess further south over the mid-latitude North Atlantic – the path of the recent storms – suggests a more complex signal. Although the number of strong winter cyclones has not increased since 1871, the mean intensity has. Notably, for very strong cyclones, the mean intensity has increased significantly. A more comprehensive study of storms affecting the UK is needed to explore these findings in more detail, but the current evidence does suggest an increase in storminess. The persistence of the recent storminess is unusual, and although clustering of storms is quite common, the continued run of deep depressions, through December, January and on into February, is not. It is this continued run of storms that has created the exceptional flooding conditions experienced in the Somerset Levels, for example. The persistence of the weather patterns affecting both the UK and also the US, where abnormally cold conditions have continued to affect the eastern and southern states through January, has raised questions about whether the jet stream is making greater excursions, north and south, and whether these waves in the jet stream are becoming more locked in one position13. This is a critical question because it raises the possibility that disruption of our usual weather patterns may be how climate change may manifest itself. The Met Office is now actively researching the best way to detect changes in the dynamics of the jet stream. Fig 21