Download presentation

Presentation is loading. Please wait.

Published byOmari Mather Modified over 2 years ago

1
Marc Schröder et al., FUB BBC Workshop, Leipzig, 05.´02 The airborne research platform of the FU Berlin: Overview of measurements taken during the BBC campaign and presentation of first products and analysis Marc Schröder, Thomas Ruhtz, Eyk Bösche, Jürgen Fischer Institut für Weltraumwissenschaften Freie Universität Berlin Germany

2
Marc Schröder et al., FUB BBC Workshop, Leipzig, 05.´02 Table of contents Overview of measurements Calibration BBC casi data catalog casi cloudmask Statistical characterisation of clouds

3
Marc Schröder et al., FUB BBC Workshop, Leipzig, 05.´02 Overview of measurements Instrument casi FUBISS classic HDRAD FUBISS extended HMR, G12 MIDAC Description Compact airborne spectrographic imager, nadir radiances (vis) FUB integrated spectrographic sys- tem (radiances): 1 nadir,1 zenith (vis), 1nadir (highvis), 1 nadir (NIR) Radiometer from the University of Heidelberg, 4 visible channels Irradiances (vis), nadir, zenith Flight attitude (20 Hz), GPS (10 Hz) Fourierspectrometer (5-17 m) Status ok ok, except for NIR ok no HMR since , GPS ok no Amount 54 G 2 G 9 M 4 G 0.5 G 1 G

4
Marc Schröder et al., FUB BBC Workshop, Leipzig, 05.´02 Calibration examplary results for FUBISS vis nadir absolute calibrationspectral calibration

5
Marc Schröder et al., FUB BBC Workshop, Leipzig, 05.´02 Calibration: Spectral comparison Hintergrund Radiative smoothing (Bounded) cascade models Multifraktalität data taken from the leg04 time: utctime: utc

6
Marc Schröder et al., FUB BBC Workshop, Leipzig, 05.´02 Calibration: Time series comparison data taken from the leg04 wavelength: 753 nm

7
Marc Schröder et al., FUB BBC Workshop, Leipzig, 05.´02 BBC casi data catalog Hintergrund Radiative smoothing (Bounded) cascade models Multifraktalität

8
Marc Schröder et al., FUB BBC Workshop, Leipzig, 05.´02 BBC casi data catalog: Track overview start time stop time section length leg01 leg02 leg03 leg04 09:30:48 10:31:17 10km length: 28.69km / sections: 2 length: 30.22km / sections: 3 length: 29.27km / sections: 2 length: 57.11km / sections: 5 Date: Leg: 02

9
Marc Schröder et al., FUB BBC Workshop, Leipzig, 05.´02 BBC casi data catalog: Images 34.2° altitude swath top of image correspondes to geograhpic north casi

10
Marc Schröder et al., FUB BBC Workshop, Leipzig, 05.´02 casi cloudmask: Algorithm development casi nadir radiances, one received over cloud, the other over meadow, normalised to the respective radiance at 780 nm define ratio: r = L(490 nm) / L(780 nm) find thresholds: cloud if r r T and cloud if L(490 nm) L T (490 nm)

11
Marc Schröder et al., FUB BBC Workshop, Leipzig, 05.´02 casi cloudmask development: Thresholds histograms of casi nadir radiances at 490 nm and the ratio r, data from , leg5 thresholds: r T = 0.5 and L T (490 nm) = 60 Wm -2 sr -1 m -1

12
Marc Schröder et al., FUB BBC Workshop, Leipzig, 05.´02 casi cloudmask development: Cloud shadow on clouds white: cloudmask with previous condition only 2nd condition: r T 1.35 and L T (490 nm) 35 Wm -2 sr -1 m -1 gray: advanced cloudmas- king technique pm, leg2

13
Marc Schröder et al., FUB BBC Workshop, Leipzig, 05.´02 casi cloudmask: Results I data from pm, leg6

14
Marc Schröder et al., FUB BBC Workshop, Leipzig, 05.´02 casi cloudmask: Results II data from , leg7

15
Marc Schröder et al., FUB BBC Workshop, Leipzig, 05.´02 casi cloudmask: Results III data from , leg1

16
Marc Schröder et al., FUB BBC Workshop, Leipzig, 05.´02 Power spectra Definition: Scale invariance: stationarity if stationary incre- ments if E(k) ~ |F(k)| 2 E(k) ~ k - < 1 1 < < m =2.52 =1.37 data from , leg3 cloud fraction b = 0.97

17
Marc Schröder et al., FUB BBC Workshop, Leipzig, 05.´02 Structure function analysis 1) (r;x) = (x+r) - (x) = i+r - i with i=1,...,N-r and N=L/l 2) ~ (r/L) (q) with q 0 Results for H(q) = (q) / q small scales r: H(q=1) = 0.47 large scales r: H(q=1) = 0.22

18
Marc Schröder et al., FUB BBC Workshop, Leipzig, 05.´02 small scales r: C(q=1) = 0.11 large scales r: C(q=1) = 0.07 Singulare measures 1) (1;x) = (x+1) - (x) = i+1 - i with i=1,2,...,N-1 and N=L/l 2) (1;x) = | (1;x)| / with = 1/(N-1) | (1;x)| 3) (r;x) = 1/r (r;x) 4) ~ (r/L) -K(q) with q 0 Results for C(q) = K(q) / (q-1) and C(q=1) = K´(q) | q=1

19
Marc Schröder et al., FUB BBC Workshop, Leipzig, 05.´02 Summary calibrated level 1b data for casi and FUBISS highvis, shortly available: FUBISS vis (nadir, zenith) delivered level 0b data to the IUP BBC casi data catalog, available for each day casi cloudmask, partly processed statistical characterisation of clouds: to be completed for days with high cloud fraction

Similar presentations

© 2016 SlidePlayer.com Inc.

All rights reserved.

Ads by Google