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  2. A stonking Greenland/Iceland high on the gfs 6z with a chilly easterly . That’ll do for starters .
  3. Suppose to have said we should all be vegans to protect the environment. As motor racing has such a low carbon footprint it is not worth giving that up.
  4. Great satellite image of the swirling low off the NW of the UK with its associated showers. And you can see the blob of cloud (with rain) already into the south of the Region and which will spoil the current sunshine here too.
  5. North Atlantic Oscillation (NAO) The NAO is a very important teleconnection for UK and European winter prospects. Recent Seasonal Model forecasts point to a positive NAO (+NAO), suggesting the winter outlook for our part of the World is looking to be dominated by cyclonic mild, wet and windy weather. This post centres on the Met Office paper titled Skillful long‐range prediction of European and North American winters and the four key oceanic and atmospheric teleconnections shown to drive or influence the wintertime NAO. You can find the full paper here. Using the Met Office’s own findings about teleconnection impact I will look at each of them in turn to try and gauge whether their current and forecast state (or phase) supports the recent seasonal forecasts of a positive NAO. Here’s a key passage from the paper: “The single most important factor for year to year fluctuations in the seasonal climate around the Atlantic Basin is the state of the North Atlantic Oscillation and its hemispheric equivalent, the Arctic Oscillation. Year to year variability in the NAO describes the state of the Atlantic jet stream and is directly related to near‐surface winds and hence winter temperatures (through advection) across North America, Europe, and other regions around the Atlantic Basin. We present estimates of the predictability of the surface NAO and winter climate from the Met Office seasonal forecast system Global Seasonal forecast System 5 (GloSea5) which has high ocean resolution, a comprehensive representation of the stratosphere, and interactive sea ice physics, all of which mediate predictable teleconnections to the North Atlantic.” For those wishing to learn more about the NAO there's a link to an informative Met Office overview here. There are also a number of other scientific papers relating to the NAO and they can be found in the Learning Area here. Before looking at the current status of each teleconnection in turn, for reference here’s the latest (Oct 2019) 3-month winter forecast from the Met Office Glosea5 model showing a +NAO: So which are the four teleconnections used in the Met Office study and which Glosea5 uses when producing its seasonal forecast? (Note: You can find a full list of variables used by Glosea5 here). They are: El Nino Southern Oscillation (ENSO), North Atlantic Ocean temperatures particularly in the sub-polar gyre, Sea-ice levels particularly the Kara Sea, Quasi-Biennial Oscillation (QBO). Focussing in on each: 1. ENSO: The ENSO state is based on the Oceanic Nino Index (ONI) which measures the departure from normal Sea Surface Temperatures (SSTs) in the ENSO 3.4 Region. El Niño is characterised by a positive ONI greater than or equal to +0.5ºC and La Nina a negative ONI less than or equal to -0.5ºC. To be classified as a full-fledged El Niño or La Niña episode, these thresholds must be exceeded for a period of at least 5 consecutive overlapping 3-month seasons. The Met Office paper states: “One source of predictability originates in the tropical Pacific. Previous studies have shown that the El Niño–Southern Oscillation [based on 3.4 Region] can drive interannual variations in the NAO and hence Atlantic and European winter climate via the stratosphere. …… this teleconnection to the tropical Pacific is active in our experiments, with forecasts initialized in El Niño/La Niña conditions in November tending to be followed by negative/positive NAO conditions in winter.” The latest 16th October ENSO update from NOAA confirms that ENSO is currently neutral, as defined above, but interestingly that over the next month will be close to the El Nino threshold and that their multi-model forecasts also keeping ENSO close to the threshold over the winter: Source: https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/lanina/enso_evolution-status-fcsts-web.pdf In their analysis NOAA say: “Many dynamical forecast models, including the NCEP CFSv2, suggest Niño-3.4 SST index values will remain near +0.5°C during the next month or so before decreasing, but remaining above zero.” And over the winter months: “…….with multi-model [forecast] averages of Niño-3.4 values remaining close to El Niño thresholds (+0.5ºC).” Source: https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/lanina/enso_evolution-status-fcsts-web.pdf My conclusion: Current and forecast ENSO conditions, whilst neutral (based on official classification), are closer to El Nino than La Nina and do not appear to be in support of the Glosea5 forecast. It could be argued they appear more favourable to supporting a negative rather than a positive NAO. 2. North Atlantic Ocean temperatures particularly in the sub-polar gyre Next a look at the second teleconnection of importance. The Met Office paper states: “……by selecting forecasts in years with a warm or cold north Atlantic subpolar gyre in November, we can examine the resulting winter signal in the atmospheric circulation. Forecasts starting from cold/warm North Atlantic states also result in winter predictions with more positive/negative NAO.” The Met Office use the North Atlantic ocean heat content (OHC) averaged over 90W-0E, 50-60N and the upper 500m of the ocean and use one of their internal models to obtain this data. I’ve not been able to obtain publicly available information that exactly matches their criteria, but instead have used the current SSTs for the area and a sub-set of the area that does have Argo OHC data averaged down to 800m. SSTs with Met Office area marked in red: Source: https://www.esrl.noaa.gov/psd/map/clim/sst.shtml Sub-set of OHC for area (data is only available for the following area shown on this map as the Northern Branch of the Gulf Stream): And here’s the latest available data for March 2019 with my estimate of the likely trend, based on previous years fluctuations, marked in red: Source: http://www.climate4you.com/SeaTemperatures.htm#North Atlantic 59 degrees north transect to 1900 m depth My conclusion: Using the above substitutes in the absence of Met Office figures is inclusive. SSTs are neutral whilst the average of the 0-800m temps of a sub-set of the area ‘might’ be trending colder which if so would be supportive of a positive NAO. 3. Arctic Sea-Ice (Kara Sea) The third teleconnection influencing the NAO is the level of Arctic sea ice, particularly in the Kara Sea to the north of Europe. The Met Office paper states: “Interannual variability of sea ice and hence surface temperature is large here and has previously been connected to the generation of large‐scale circulation anomalies. [The research shows] the association between sea ice anomalies in this region [45-75E, 67-80N] in November and the subsequent winter circulation in forecasts and observations. As identified….. low/high sea ice concentrations in the Kara Sea in November precede negative/positive NAO anomalies, with anomalous pressure gradients over northernmost Europe and the East Atlantic.” Here are the current SST conditions in the area on the 12th October. The Kara Sea is circled in red and SSTs are 2C to 3C above the long-term average for the time of year: Source: http://ocean.dmi.dk/satellite/index.uk.php A look at current sea ice cover in the Arctic also shows that extent is well short of the 1981-2010 long-term average: Source: https://nsidc.org/data/search/#keywords=sea+ice/sortKeys=score,,desc/facetFilters=%7B%7D/pageNumber=1/itemsPerPage=25 My conclusion: If these conditions were to persist into November, this teleconnection would be supportive of a negative NAO. Clearly an update on the status of this teleconnection is required as we move into November. 4. Quasi-biennial Oscillation (QBO) Our final teleconnection influencing the NAO arises from the phase of the quasi‐biennial oscillation (QBO) in the tropical lower stratosphere. Basic info on the QBO can be found here. The Met Office paper states: “Interannual variability between westerly and easterly phases of the QBO [at 30hPa] has long been known to influence the troposphere in the Atlantic sector….. with westerly QBO being associated with a stronger extratropical jet, particularly in early winter.” At the moment the easterly QBO zonal winds are slowly descending but for the last several weeks have stalled somewhat at 20hPa. This is illustrated on the latest chart from the NASA website with the small circle in red. For interest I have circled the unique eQBO of 2016 that failed to descend and reverted to wQBO. Source: https://acd-ext.gsfc.nasa.gov/Data_services/met/qbo/qbo.html#intro Extrapolating the latest NOAA 30mb QBO data from Jan to Sept 2019 suggests the QBO at 30mb won’t turn easterly until Feb 2020. Monthly data: 9.02 9.25 11.82 13.36 14.59 14.36 10.96 9.97 8.25 However, in a June 2018 paper titled: Surface impacts of the Quasi Biennial Oscillation (full paper here) it was found that “…..in early winter (December), responses to the QBO show maximum sensitivity at ∼20 hPa, but are relatively insensitive to the QBO winds below this until late winter. The impact is that Atlantic/European response is shifted eastward compared with the normal +NAO pattern.” My conclusion: The influence of the present westerly QBO will be waning as the easterly zonal winds descend. But possibly more important, if the research mentioned above is taken literally, then the early winter surface response to the QBO shows maximum sensitivity to what’s happening in the stratosphere at around 20hPa, which is already easterly. It could therefore be argued that this teleconnection is supportive of a negative NAO. Summary Whilst the publicly available data used in my analysis is clearly going to be somewhat unsophisticated when compared with the comprehensive input data that Glosea5 would use, I nevertheless find it interesting that the current and forecast state of key teleconnections may not be completely in agreement with forecasts of a positive NAO as we go into winter. I’ll revisit the status of the four teleconnections again in November to check for any developments. Comments welcomed.
  6. I like the WAA being to the west of Greenland, and not to the east; it's better than seeing a quasi-stationary intense depression sitting there...isn't it? And, who knows what part the residual heat, over mainland Europe'll, will play as we approach winter...?
  7. It seems like his want to help protect the environment and his career are coming increasingly into conflict in his mind. Maybe a surprise retirement, or move to Formula E?
  8. No need to apologise Karl, the models make mugs of the best of us!! In fairness you have regularly stated that there are a fair few ensembles running quite warm. This is still one of my concerns with the new GFS model, that it will be sending us up the garden path again, by constantly overplaying cold sypnotics! Some of us are perhaps a little guilty of overstating incoming cold snaps, when in reality it's still a little on the early side just yet! Perhaps it's the coldie in us that gets us a little overly excited. Looking at the extended ECM mean out till November, shows the mean around 1C for the Birmingham area, so it's nudging down a little..... Problem is there are a good 60% of runs going above this, the SLP is around 1016mb,so perhaps drier conditions still the order of the day..... And let's remind ourselves.... It will still be Autumn..... Plenty of time for things to change..... For better of for worse I may add!
  9. I'm not sure how the video above says anything about the protests not being peaceful. It was the protester that got dragged down and beaten! Anyway, yeah, stupid move targeting public transport like that. I get that they want attention and headlines, but there are better ways to achieve that.
  10. A low of 7.5°C this morning. A 3.8mm shower makes today the 15th consecutive day of rain. Temp currently at 12.4°C. According to the forecast, winds should be gusting to 30mph here, yet it's almost calm.
  11. Today
  12. More than 500 people misunderstand climate change « RealClimate WWW.REALCLIMATE.ORG A consensus is usually established when one explanation is more convincing than alternative accounts, convincing the majority. This is also true in science... These people have little or no history of climate research and many have links to "think tanks" that are committed to denying the effects of AGW. They are going to start lobbying both the UN and the EU.
  13. Forgot to mention, I was thinking of Nathan Rao, check him out. Utter #$%$#
  14. Well the forecasts for Cairngorm and Ben Nevis summits look pretty wintry. Cairn Gorm Summit weather WWW.METOFFICE.GOV.UK Cairn Gorm Summit 7 day weather forecast including weather warnings, temperature, rain, wind, visibility, humidity and UV Ben Nevis weather WWW.METOFFICE.GOV.UK Ben Nevis 7 day weather forecast including weather warnings, temperature, rain, wind, visibility, humidity and UV
  15. Well Mark...By disrupting the 'greenest' part of the capital's public transport-network, they'll be alienating the very folks from who they want support? Idiots!
  16. Low pressure over Latvia, Lithuania pretty much corresponds with the GFS sea level pressure chart. Sat image from 10am this morning.
  17. Thursday 17th October 2019 Turning mainly clear overnight, quite chilly, just missing a ground frost. Sunny start this morning. 24-hour maximum 14.0c 24-hour minimum 3.2c Minimum temperature on grass 0.5c. Maximum wind gust: (Midnight to Midnight) 15.4mph W Rainfall total: 0.0mm Conditions at 09:00 GMT 2 Oktas Cumulus. Visibility >10 miles Temperature: 6.9c Humidity: 95.5% Wind Direction: SSE Force 3 Barometer 1001.5mb rising slowly. Yesterday. Mostly cloudy overnight. Light rain through the early hours. Dawning overcast, a little light rain. Brighter spells developing shortly after the observation. After a mostly cloudy morning the afternoon saw some sunny spells.
  18. As unreliable as Accuweather is, perhaps theres some truth with the storms? A repeat of 13-14 would be a horror zone. Perhaps the worst winter ever.
  19. Quite nasty scenes on the underground from what i saw on the news very silly idea to target the underground at rush hour
  20. He looks absolutely nothing like how I pictured him haha. I remember reading his predictions and forecasts in the express (My father used to buy it) and it would make me physically angry how often he got it completely wrong and was continuously given a platform to spout his nonsense.
  21. So nice to feel cold again -3.5C in Braemar this morning!
  22. I'm pretty sure it snowed a fair bit Winter 2012-13 down here..I seem to remember the run up to Xmas being very seasonal and further events in February. Could be wrong though - so hopefully a precursor of whats to come?
  23. Maybe this year's thunderstorm season is still not quite over: But, the GEFS 00Z ensembles are so 'messy', it's not easy to see what, if anything, has much support, either way? Och well...back to the Guess Chamber?
  24. HAHA! You sir deserve a medal. Here is with some sort of papier mache orange turd attached to a globe (think its meant to be the sun and a solar filament)
  25. A dry, mainly clear and cool night with a slight ground frost. Dry and sunny so far this morning. At 0800 g.m.t Temp; 5.8c 24 hr max; 12.4c 24 hr min; 3.7c Grass min; -0.9c Rainfall in 24 hrs ending 0800 g.m.t; 0.4 mm Mean wind speed; 9 mph S 1 okta Ac and St fractus Vis; 9 km.
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