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Showing posts with label DMI. Show all posts
Showing posts with label DMI. Show all posts

Thursday, September 12, 2013

Sequel to: Anthony Watts visits Greenland and finds Airport UHI disease!

Sou | 1:16 AM Go to the first of 17 comments. Add a comment

Update - see below for Anthony Watts' acknowledgement.



Who could forget Anthony Watts finding UHI disease at Maniitsok airport in Greenland?


Greenland sets new record high temperature this year: Confirmed


Here's the sequel. From Jason Semonow, Capital Weather Gang at Washington Post:
Today, John Cappelen, senior climatologist at the Danish Meteorological Society, emailed me to let me know the record high of 25.9 C (78.6 F) set on July 30 at Maniitsoq stands.
“I have now accepted the record at Maniitsoq based on further analysis,” Cappelen said.
At issue was whether the temperature measurement, taken at an airport location, was legitimate. Artificial heat sources at airports can sometimes corrupt temperature readings.
“We were faced with two options,” Coppelen explained. “We could reject the observation, or we could approve it. If we chose to overrule it, it could be based on two things. One was a faulty sensor/station…and that was not the question – the sensor measured exactly as it should. The second was if we had suspected that extreme local conditions played their part. Here the situation is more debatable, because the station is an airport station that is not necessarily completely optimal in relation to international guidelines for climatological data measurements.”
But Coppelen said the mere fact the temperature was recorded at an airport is not a reason for it be thrown out as few existing weather observing stations in Greenland are ideally sited.
“Within the World Meteorological Organization (WMO) prescribed practices, among other things, measurements – as an example – should be taken over a short lawn,” Coppelen said. “This can be done in Denmark almost anywhere, but in Greenland almost no places.”
Coppelen concluded: “The station in Maniitsoq is within the quality frame practicable/possible for this type of meteorological measurements in Greenland, so it is approved. Alternative would be to question many observations and weather records for Greenland…it doesn’t make sense

DMI press release here.

As a reminder, I posted some suggestions for the weather station siting since Anthony Watts complained it was no good, pointing out the other suggestions were even darker, with not a lawn in sight.




Should we anticipate an article by Anthony Watts acknowledging the record temperature set at Maniitsok in Greenland this year?

Update 

Friday 13 Sept 3:39 pm: 
Anthony Watts has posted the fact that a record has been recorded in his latest WUWT Hot Sheet (archived here).  He hasn't updated his original article (archived here). H/t Thomas Murphy.

The original HotWhopper article and the follow up.

Tuesday, August 13, 2013

Anthony Watts of WUWT gets noticed by Capital Weather Gang at The Washington Post

Sou | 4:17 AM Go to the first of 7 comments. Add a comment

Update: There is a sequel :)


Anthony Watts of WUWT has hit the big time, being noticed by The Washington Post.  But he's not the only one :)

I didn't mention what prompted Anthony's humourous efforts to find something wrong with a weather station in Greenland the other day.  It was a short article by Jason Samenow of Capital Weather Gang at the Washington Post observing that a record temperature had been reported by the Danish Meteorological Institute.

Jason was subsequently plagued by tweets from Anthony Watts, demanding he issue a "retraction".  Not once, not twice but three times.  Anthony also sent an email.  Anthony really got his knickers in a twist over that one.  Here are his tweets:




The Maniitsok temperature reading is valid but may or may not reach the record books


Jason Samenow has now posted a response.  He did what Anthony doesn't seem to have done.  He wrote to John Cappelen, data management specialist and senior climatologist at DMI.   Cappelen replied that the reading was valid but because the weather station doesn't comply with all WMO standards, it might not get into the record books.  He wrote: "It is generally very hard to follow the WMO standards in all details in arctic areas, but this sensor is placed so influence from the surroundings can have affected the reading in a way, so the reading maybe will have to be rejected." He will let him know once they've considered the matter and made a decision.  You can read the reply at Capital Weather Gang in Washington Post.

The only reason I know all this is because I happened to look at the live stats for my blog and noticed a sudden influx of visitors.  Went to see what the fuss was all about and discovered that @capitalweathergang had retweeted this:

John Samenow also referred to yours truly in a comment underneath his article.  @capitalweathergang has a few more followers and Washington Post has a few more readers than both HotWhopper and WUWT.  Some of them came here for a look see.  Nice - and thank you to @greenoctopus :)

(As usual, Anthony can't wait to let his readers know that he has some clout in cyberspace.)


PS Now we wait with bated breath for Anthony tell the Japan Meteorological Agency why all the weather stations in Japan are wrong! (H/t @shawnmilrad).

PPS Without a smidgen of self-awareness, Anthony's headline for his article is "Shoot first ask questions later".  Yet it was he who shot first without asking questions, and it took Capital Weather Gang to ask the question of the people who would know the answer.

Sunday, August 11, 2013

WUWT is below average in the Arctic

Sou | 1:52 PM One comment so far. Add a comment

Anthony Watts does come out with some beauties from time to time.  That's being generous.  He comes up with doozies almost every time he puts fingers to keyboard.

Today he's blogged an article telling everyone that the climate predictions and projections for 2100 haven't yet all come to pass, and it's already 2013.  I mean, there's only 87 years to go.  All those scientists must be wrong.

I won't bother going into detail about everything he's written.  I'll just mention a few things in passing.  For example, I notice he switched to the USA part way through and ignored the rest of the world.  He put up statistics on hurricanes that were still hurricanes by the time they made landfall in the USA.  That way he could avoid Sandy as well as all the other tropical cyclones in the world. And why he put up tornadoes I don't know, because the science isn't in on what will happen with tornadoes in a warmer world.  He put up winter snowfall in the USA but failed to mention the record melt from April to May this year.  He most certainly avoided mentioning Australia's Angry Summer and all the other signs of global warming in recent years.  It would have spoilt the story he's spinning and upset the punters no end.

What you won't have noticed (because what self-respecting person reads Anthony Watts' blog, bar we blog war people) is that Anthony doesn't seem to know what an average is.


The Arctic is getting hotter


Anthony seems to be trying to tell his readers that the Arctic hasn't warmed, despite the fact that sea ice is disappearing at a faster rate than projected.

Here is a plot of temperature for the Arctic from GISTemp.  It shows the anomalies from the 1951 to 1980 mean for latitudes 64N to 90N.  The average annual temperature for the Arctic has risen by more than 3 degrees Celsius since the late 19th century, by almost one degree since the Arctic warm spell in the 1930s and by almost two degrees since the early 1970s.

Data Source: NASA

Here's a chart showing the amount of sea ice in the Arctic (blue) and Antarctica (dark red) in the month of their respective annual minima for the period since 1979, as well as the total sea ice (green).  Of course the total isn't the total at a real point in time because the months of the minimum are different north and south.

Data Source: NSIDC


What is the "climatic normal" at WUWT?

Getting back to why I said that Anthony is trying to kid people that the Arctic isn't warming.  He put up an animated version of the chart below, showing each year from 1958 onwards.  The chart is described by DMI as the daily mean temperatures for the Arctic area north of the 80th northern parallel, plotted with daily climate values calculated from the period 1958-2002.  (Note that this is a smaller area that the GISTemp chart above, which is north of the 64th northern parallel.)  Anyway, Anthony claimed:
The DMI plot of Arctic temperature for 2013 (at the end pause of this animation) hasn’t gone above the climatic normals since this dataset began in 1958.

Source: Danish Meteorological Institute

Really?  It's a very mixed up sentence to start with.   I assume by "climatic normal" he means the average as calculated by DMI, which is the mean of the period 1958-2002 (the solid green line).  If Anthony means that no year has gone above the "climatic normal" then it doesn't make sense.  The temperature has to have gone above normal at least half the time between 1958 and 2002 - right? Or if not as much as "half the time", considerably above normal some years.

If he means that 2013 hasn't gone above the mean, then he's blind as a bat.

If he expects the Arctic Basin north of 80N to get much warmer than freezing in summer time, then he doesn't know much about the Arctic.  Remember, we're talking above the 80th parallel here.  If your geography is a bit rusty, here is the region we're referring to.  It's the bit inside the circle marked "80".  It's not even all of the Arctic Ocean, and very little land:

Source: Wikipedia


Does Anthony think his chart is an actual physical mean temperature of the Arctic?

I wonder does he also realise that the data is from a model.  It's data assimilation and reanalysis - as described here.  DMI warns readers to not use the charts as a measure of actual physical mean temperature but to use them to compare years.  Here's what DMI say (my bold italics):
The temperature graphs are made from numerical weather prediction (NWP) "analysis" data. Analyses are the model fields used to start NWP models. They represent the statistically most likely state of the atmosphere, given the information available to make the analysis. Since the data are gridded, it is straight forward to deduce the average temperature North of 80 degree North.
However, since the model is gridded in a regular 0.5 degree grid, the mean temperature values are strongly biased towards the temperature in the most northern part of the Arctic! Therefore, do NOT use this measure as an actual physical mean temperature of the arctic. The 'plus 80 North mean temperature' graphs can be used for comparing one year to an other....
The process of making the analysis is called "data assimilation". In an NWP data assimilation system many, very different types of observations and other information are combined in a statistical manner. In practice the assimilation is done via adjusting a recent NWP forecast, a so-called first guess. Because the data assimilation system knows about interrelations of different model variables, assimilation of for example a pressure observation, will adjust not only the pressure, but also wind and temperature. Precisely how much weight to give different types of observations, and how far to distribute their effect in the first guess field, is deduced statistically. The analysis is the maximum likelihood estimate of the state of the atmosphere, provided the statistical information is correct.
An NWP analysis is based on vastly more information than available from any single observing system. Data from ground, aircraft, bouys, ship, satellites, radiosondes, etc. are all combined to adjust the first guess field. As a consequence the quality of an analysis is much better than what can be obtained from gridding, or treating in other ways, data from a single or a few observing systems.
In the plot, the red curve is based on the average 2 m temperatures north of 80 degree North, from the twice daily ECWMF analyses. These are gradually becoming better and more detailed, as the NWP model system at ECMWF is improved with time. That is why the name shift with time (e.g. from T799 to T1279 in year 2010).
... The green curve is based on ERA40 data for the period 1958 to 2002. ERA40 data are in fact analyses, made in the same way as above, but done as a hind-cast, using a fixed version of the NWP model, and spending time on carefully validating and eventually correct or remove all observations found to be in error, before the data assimilation. These, so-called "re-analysis", data represent our best estimate of the properties of the atmosphere for the period they cover.

I think that's about enough on Anthony's misdirection for one blog article, don't you?