Data trends at meteoLCD: 1998 to 2013


Trends computed from yearly averages at meteoLCD, Diekirch, Luxembourg.
Graphs may be freely copied and used, under the condition to cite:
MASSEN, Francis: Data trends at meteoLCD, 1998 to 2013. http://meteo.lcd.lu

Older trends are here!

Most important conclusions for the last decade (2004 to 2013) linear trends:

1. Solar dimming is -26 kWh*m-2*decade-1  [- 2.4 %]
2. Local temperatures are declining by -0.15 C*decade-1  [ - 1.5 %]
3. There is no trend in daily min. temperatures, DTR and daily max. show small decrease
4. The winters are cooling by -0.71 C*decade-1 [- 24.7%]
5. Ground O3 increases by 2.1 ug*m-3*decade-1 (suspicious!),  thickness of ozone layer increases by 0.6 DU*decade-1 [+ 0.2%]
6. Local CO2 mixing ratio increases by 3.2 ppmV*decade-1 (suspicious!), by +0.98 ppmV*y-1 from 2002 to 2012 and +0.83 ppmV*y-1 from 2002 to 2013
7. The biologically effective UVB dose declines by 3 eff. Wh*m-2*decade-1 [- 2.3%]
8. The UVA dose declines by 0.3 kWh*m-2*y-1[- 4.0%]
9. Precipitation (rainfall) increases by 77 mm*decade-1 [+ 1.3%]
10. Energy content of moist air (enthalpy) declines by -0.6 KJ*Kg-1*decade-1 [-2.1 %]
11. NO2 concentrations increase by 6 ug*m-3*decade-1 (suspicious) [+ 31%]
12. NO concentrations decrease by -3 ug*m-3*decade-1  [-30 %]

Ground Ozone [ug/m3]

("bad ozone")

From 1998 to 2013: negative trend: -0.7 ug/m3 per year

1998-2013 mean +/- stdev:
38.8 +/- 6.9 ug/m3
  

Attention: there are about 15% missing data in 2013 due to frequent sensor failures, so the 2013 data point and the 2004-2013 trend line are suspicious!

 

See [1] [2] [3] [17]

Total Ozone Column [DU]
("good ozone")

Mean +/_std: 320.9 +/- 45.8 DU
positive trend: +1.6 DU per year
, -0.1 since 2002
(Uccle
 gives +0.95  for the 1998-2010 period) (see also [16])

Calibration multiplier to apply if Uccle Brewer #16 is the reference:
1998 to 2007: * 0.95
2008 to 2010: * 1.00
2011              : * 1.06

2012              : * 1.04
2013              : * 1.06 (provisional)

2
013 common days measurements results:
Diekirch   = 321.6 DU
Uccle DS = 342.0 DU
Uccle data are from WOUDC (stat.53, Brewer#16, provisional as Dec. data not yet available)

1998 to 2012 mean +/- stdev:
Diekirch: 323.8  +/- 15.5
   Uccle.:  328.8 +/- 3.5
(Uccle without 2009/10/11
)
                                   

See [4] [8] ([8] shows strong positive trend starting 1990 for latitudes 45-75 North, Europe): [27] give +1.32 DU/y at the Jungfraujoch for 1995-2004.
See also recent EGU2009 poster [16].

CO2 mixing ratio in ppmV 

The 1998-2001 data are too unreliable to be retained for the trend analysis.

2002 to 2013
mean +/- stdev:: 408.4 +/- 5.3 ppmV
trend = +0.83 ppmV per year

2007 to 2013 mean +/- stdev:: 410.9 +/- 4.2 ppmV
trend: - 0.77 ppmV per year !

The sharp plunge and negative trend should be taken with caution; there was a change in the calibration gas the 21 Jan. and the primary standard used (600 ppmV) has an accuracy of 1%. All readings <= 370 have been discarded.
The 2013 average of 402.9 ppmV is close to those measured by the German stations of Hohenpeissenberg (HPB 400.4, trend +2.5) and Ochsenkopf.(OXK 399.9, trend + 1.67).[34]
                                       

The right picture shows the asymptotic CO2 values (CO2wind) derived from the model published in [21] .
The blue upper curve shows the yearly mean values at Diekirch; the middle red curve the asymptotic CO2 values that would exist if wind velocity was infinite, and the lower green curve the yearly averages at Mauna Loa, augmented by +1.8 ppmV to respect the latitudinal gradient of approx. 0.06 ppm per degree.
The asymptotic mixing ratios are reasonably close to those of Mauna Loa (adjusted) up to 2012; the yearly trends calculated from the mean and asymptotic values at Diekirch are noticeably lower (0.83 and 0.88 ppmV*y-1) than the MLO trend of 2.05.

Compared trends from 2006 to 2012 for EU sites:
Ochsenkopf (OXK): 0.68
Hohenpeissenberg (HPB): 1.68
Diekirch: 1.14

See also [25]

 

The 2013 CO2 data clearly show the summer-time lows, mostly due to the increased photo-synthesis. The amplitude 2A of the best-fit sinusoidal model is about 12 ppmV. The paper [35] gives an annual swing of ~12 ppmV whereas the Hohenpeissenberg (lat. 47.8) and Ochsenkopf (lat. 50)  measurements suggest about 20 ppmV. A paper discussed at [36] gives an 2A amplitude of about 12 ppmV at ~5km altitude and 50 latitude North. It seems that the annual swing is increasing since 1960 mostly due to enhanced biosphere activity.

Air temperature [C]

Trend from 1998 to 2013: +0.0045 C per year, practically flat!

1998 to 2013 mean +/- stdev::
10.29  +/- 0.45 C                                        

2002 to 2013:
10.34 +/- 0.50 C

The sensor has not been moved since 2002!

Strong cooling trend from 2002 to 2013:
meteoLCD:     - 0.23C/decade
Findel:              -0.46C/decade


Global NH Land temperature trends:
UAH (satellite)   : + 0.03C/decad   [26]
CRU (Hadcrut4): -  0.02C/decad.  [18]

Highest decadal Central England warming trend from 1691 to 2009: +1.86C/decade for 1694-1703!
See also [15] (which may be obsolete)

Diurnal Temperature             
Range (DTR)  [C]

DTR = daily max - daily min temperature

For 2002 to 2013:
Small negative trend: -0.04 C per year
.
Findel DTR trend is -0.05 C per year
(plot shows rounded numbers)

1998 to 2012 mean +/- stdev:: 8.48 +/- 0.55 C         

2002 to 2013: daily max trend slightly negative, daily minimum trend flat, so DTR trend = daily max. trend.!
 
A fingerprint of global warming is that daily minima increase more than daily maxima. Clearly the data do not show this!

The BEST data [29] including 2013 are not yet available.

See [5], [13] and [30]

.
Winter temperatures [C]

Contrary to what is often suggested in the media, winters are cooling since 2002. The cooling rates per decade are:

Diekirch:   -0.46 C/decade
Findel:       -0.76 C/decade
Germany:  -0.94 C/decade [31] (not on plot)

The plot shows the mean temperatures of December (from previous year), January and February. It also shows in brown (right Y-axis) the NAO index for the months Dec to Mar [32]

The North Atlantic Oscillation clearly influences our winters; the correlations between the 3 different DJF series and DJFM_NAO are 0.76, 0.77 and 0.79, all significant at the 5% level. The NAO trend is also negative for the 2002 to 2013 period.

Total Yearly Rainfall [mm]

1998 to 2013 mean +/- stdev::mean :
706.9 +/- 143.5 mm .
Negative trend of -14.7 mm/year        

2003 to 2012:
653.7 +/-
119.2 mm 
Positive trend of +5.4 mm/year                                

Rainfall in Diekirch may be very different from that at the Findel airport ! Totals for 2013:
Diekirch = 680, Findel = 960, Trier = 791 mm.

Acceptable simple model: Sinus function of 7 years period (R2 = 0.36). Model more or less correctly reflects rising and falling precipitation.

[6]
gives medium term periods of 10 to12 years for the  region from England to eastern Germany.

Solar energy on a horizontal plane

mean +/ std:: 1109.8 +/-46.5  kWhm-2

Visible negative trends:
1998 to 2013: -2.8 kWhm-2y-1
2004 to 2013: -2.6 kWhm-2y-1
(solar cycle #24 begins Jan. 2009).

According to Scafetta's sensitivity k1s the period 2004 to 2013 should cause a cooling of -0.016 Ky-1  ([20]). The meteoLCD observations show from 2004 to 2013 a very close cooling of -0.015 Ky-1 , .
(see Addendum 1)

Helioclim satellite measurements show ongoing solar dimming over Luxembourg for 1985 to 2005  [33] (see graph)
[14] finds 0.7 Wm-2y-1 for West-Europe 1994-2003 , meteoLCD +1 Wm-2y-1 for 1998-2003.See also [9]

Sunshine duration
(derived from pyranometer data by Olivieri's method)

Totals for 2013:
meteoLCD: 1460.0 hours (215m asl)
Findel:          1632.7 hours (365m asl, Campbell-                                                                        Stokes)
Trier:             1499.8 hours (279m asl)

Trend: - 2.7 hours per year

Mean +/- stdev:
1998 to 2013:  1652.9 +/- 171.3 hours
2004 to 2013:  1636.5 +/- 116.6

Note important negative trend from 2004 to 2013: - 16.3 hours per year = 163 hours/decade!

The decline from 2012 to 2013 is -10.8%, to be compared to the data from the Fraunhofer Institut which give a decline of -10.6 % of the German PV "Volllasttunden" [37]

See paper [23] by F. Massen comparing 4 different methods to compute sunshine duration from pyranometer
 

Biologically eff. UVB dose on a horizontal plane in kWh/m2  

Practically flat trend line for the whole period.

mean +/- stdev:
1998 to 2013: 0.130 +/- 0.009 eff. kWh*m-2y-1
2004 to 2013: 0.129 +/- 0.005

Practically flat trend from 1998 to 2013, but
visible negative trend of - 0.3 eff. Whm-2y-1 from 2004 to 2013, in
accordance to the dimmimg measured  by the pyranometer over the same period. So dimming is confirmed by both pyranometer and UVB sensor

See [10] and [22] (poster finds slight positive trend in June (+2%) and negative trend in August (-1%), no trend for other months, for period 1991 to 2008)

The decrease in biologically effective UVB is also consistent with the increase of the total ozone column [28]
 

UVA dose on a horizontal plane in kWh/m2 

Positive trend: + 0.2 kWh*m-2*y-1, essentially caused by the suspiciously high 2010 reading. Negative trend of -30 Wh*m-2*y-1 since 2004, consistent with the pyranometer and UVB data.

mean +/- stdev:
1998 to 2013  54.3 +/- 4.8 kWh*m-2*y-1
2004 to 2013: 54.7 +/- 4.1

The exceptional high 2010 value (which is an extrapolation due to 8% missing data) is  dubious.
Omitting the 2010 data, the 2004 to 2013 negative trend is - 285 Wh*m-2*y-1

The 3 independent measures of Solar energy, UVA and UVB dose all document a solar dimming since 2004.

NO concentration in ug/m3
 

The 1998-1999 data are too unreliable to be retained.

2000 to 2013: trend: - 0.3 ug*m-3*y-1
2004 to 2013 rend:   idem

mean +/- stdev:
2000 to 2013: 9.2 +/- 1.8 ug/m3
2004 to 2014: 8.5 +/- 1.5

Many missing data from 2011 to 2013 ( 25%, 21% , 8%) so be careful! All these concentrations are very low! Luxembourg-City has a background of 25-30 and rural Vianden (Niklausberg) one of 2.5 (approx. 2013 values from [39])

see [11] which gives ~30% reduction from 1990 to 2005 for the EU-15 countries.

NO2 concentration in ug/m3
 

The 1998-1999 data are too unreliable to be retained.

2000 to 2013: trend: + 0.3 ug*m-3*y-1
2004 to 2013 rend:   + 0.6

mean +/- stdev:
2000 to 2013: 22.5 +/- 3.9 ug/m3
2004 to 2014: 22.7 +/- 4.5

Many missing data from 2011 to 2013 ( 25%, 21% , 8%) so be careful! All these concentrations are low! Luxembourg-City has a background of 58 and rural Vianden (Niklausberg) one of 9.4 (average since 1988) [38]

 

Enthalpy of moist air in kJ/kg
 

See [24] on how the energy content of moist air is calculated. Several authors, as Prof. Roger Pielke Sr. insist that air temperature is a poor metric for global warming/cooling, and that the energy content of the moist air and/or the Ocean Heat Content (OHC) are better.
Mean yearly moist enthalpy values are very close, but they may change from zero up to 60 Kj/kg during a year. Moist enthalpy can not be calculated for temperatures <= 0 C.

mean +/- stdev:
2002 to 2013  28.1 +/- 0.7 kJ/kg
2004 to 2013: 27.9 +/- 0.6
                       
Trend is clearly negative: -0.1 KJ/kg per year (or 0.06 for last  decade) which is consistent with the trends in temperature, solar energy, UVA and UVB doses.
 

 

   

References:

1 Europe's Environment 4th AR (2007) Fig. 2.2.3 http://reports.eea.europa.eu/state_of_environment_report_2007_1/en/Belgrade_EN_all_chapters_incl_cover.pdf
2 EPA: Ozone trends. http://www.epa.gov/airtrends/ozone.html
3

Jonson et al: Can we explain the trends in European ozone levels? Atmos. Chem. Phys. Discuss., 5, 59575985, 2005. http://www.atmos-chem-phys-discuss.net/5/5957/2005/acpd-5-5957-2005.pdf

4 Ozone trends at Uccle  http://ozone.meteo.be/ozone/trends.php
5 Rebetez, Beniston: Analyses of the elevation dependency of correlations between sunshine duration and diurnal temperature range this century in the Swiss Alps. 1998.
6 R.G. Vines, CSIRO: European rainfall patterns. International Journal of Climatology, vol.5, issue 6, p. 607-616.
7 http://global-warming.accuweather.com (15 Jan 2009).
8 J.W. Krzyscin, J.L.Borkowski: Total ozone trend over Europe: 1950 - 2004. ACPD, 8, 47-69, 2008.
9 NASA: Solar Physics: The Sunspot Cycle.
10 de Backer et al: ftp://ftp.kmi.be/dist/meteo/hugo/posters/20080630tromso_hdb.pdf (temporarly unavailable)
11 EEA: Emission trends of NOx 1990 - 2005
12 L. Motl: http://motls.blogspot.com/2009/12/uah-msu-temperatures-for-2009-and.html . Dec.2009
13 K. Makovski: The daily temperature amplitude and surface solar radiation..Dissertation for the degree of doctor of sciences. ETHZ 2009.
14 A. Ohmura: Observed long-term variations of solar irradiance at the earth's surface. Space Science Reviews (2006) 125: 111-128
15 J. van Oldenvorgh: Western Europe is warming much faster than expected. Clim.Past. 16Jan.2009
16 Van Malderen, De Backer, Delcloo: Revision of 40 years of ozone measurements in Uccle, Belgium. Poster, EGU2009, Vienna.
17 EEA: Air pollution by ozone across Europe during summer 2009
18 Climate4 you: Global temperature trends
19 Lindzen & Choi: On the determination of climate feedback from ERBE data (GRL, 2009)
20 Scafetta, N.: Empirical analysis of the solar contribution to global mean air surface temperature change. Journal of Atmospheric and Solar-Terrestrial Physics, 2009 (doi:10.1016/j.jastp.2009.07.007)
21 Massen, F., Beck, E. :Accurate estimation of CO2 background level from near ground measurements at non-mixed environments
in: Leal, W., editor: The Economic, Social and Political Elements of Climate Change
Climate Change Management, 2011, Part 4, 509-522. Springer. DOI: 10.1007/978-3-642-14776-0_31
22 De Backer & Van Malderen: Time series of daily erythemal UVB doses at Uccle Belgium. Poster, July 2009.
23 Massen, F.: Sunshine duration from pyranometer readings, 2011
24 Massen F.,  Calculating moist enthalpy from usual meteorological measurements (July 2010) and Calculating moist enthalpy revisited (Sep. 2010)
25 CDIAC: Online Trends
26 UAH MSU data: http://vortex.nsstc.uah.edu/public/msu/
27 Vigouroux et al:  Evaluation of ozone trends from g-b FTIR observations. Atmos. Chem. Phys., 8, 68656886, 2008
28 UNEP, Scientific Assessment: Stratospheric Ozone and Surface Ultraviolet Radiation
http://ozone.unep.org/Assessment_Panels/SAP/Scientific_Assessment_2010/04-Chapter_2.pdf
29 http://berkeleyearth.lbl.gov/regions/luxembourg
30 K. Makowski: The daily temperature amplitude and surface solar radiation. Dissertation ETH Zrich #18319, 2009
31 http://de.wikipedia.org/wiki/Zeitreihe_der_Lufttemperatur_in_Deutschland#Winter
32 Tim Osborne: NAO data (http://www.cru.uea.ac.uk/~timo/datapages/naoi.htm)
33 Helioclim satellite measurements of solar irradiation at http://www.soda-is.com/eng/services/services_radiation_free_eng.php
34 http://www.esrl.noaa.gov/gmd/
35 http://www.atmos.ucla.edu/~qli/publications/Jiang_2011_GBC.pdf
36 Fung: A Hyperventilationg Biosphere (Sep. 2013)
37

Fraunhofer Institut Stromproduktion : http://www.ise.fraunhofer.de/de/downloads/pdf-files/aktuelles/stromproduktion-aus-solar-und-windenergie-2013.pdf

38 EEA interacive map. http://www.eea.europa.eu/themes/air/interactive/no2
39 Portail de l'Evironnement: http://www.environnement.public.lu/air_bruit/dossiers/PA-reseaux_mesure_air/reseau_automatique/resultats_mesures_live/index.html
 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

   

          

 


Addendum 1
updated!
Lindzen & Choi [19] define the non-feedback climate sensitivity as ΔT0 = G0*ΔQ, where G0 = 0.25 Wm-2 and ΔQ is the change in radiative forcing. A change of -2.6 kWh*m-2y-1  (period 2004 to 2013) corresponds to ΔQ = - 2600/8760 = -0.297 Wm-2 and should yield a cooling of  ΔT0 = -0.25*0.297 = -0.84 K (or C).per year.

Scafetta [20] defines a climate sensitivity in respect to changes in solar radiation by k1s = ΔT/ΔF and finds k1s = 0.053. Our data for the full period 2004 to 2013 give ΔT/ΔF= - 0.0154/(-0.297) = 0.052, a value practically identical to that of Scafetta!.

Summary for the 2004 to 2013 period:
 
meteoLCD (observations) ΔT/ΔF = 0.052 K/(Wm-2y-1) ΔT = - 0.0154 Cy-1
ΔF = - 0.297 Wm-2y-1
Lindzen & Choi G0 = 0.25 ΔT = - 0.84 Cy-1 (computed)
Scafetta k1s  = 0.053 ΔT = -0.016 Cy-1 (computed)

 

Addendum 2

(to be updated!)

It makes for an interesting exercise to compare the influence of mean yearly solar forcing on moist enthalpy and air temperature for the decade 2002 to 2011.

Both air temperature and moist enthalpy are positively correlated to changes in solar forcing ( = mean solar irradiance). Neither correlation is significant at the p = 0.05 level, and both correlation coefficients are very close (R2 = 0.096 and 0.084).

A change of 1 Wm-2 of solar irradiance would cause an average heating of 0.025 C per year; a change of 1 kJ/kg of moist enthalpy would cause about 0.031  C per year, numbers of similar magnitude.

So even if the period 2004 to 2011 does not validate Scafetta's k1s sensitivity, the full decade 2002 to 2011 gives numbers of a comparable magnitude. Possibly taking into account some lag (as for instance 4 months for temperature lagging solar forcing) would change these numbers.

 

 

 

 

 


file: meteolcd_trends.html

francis.massen@education.lu
last revision: 07 Feb 2014