Closed SibylleK closed 1 year ago
https://github.com/wmo-im/CCT/wiki/Teleconference.2&3May.2023 notes: Sibylle presented the proposal; discussion about using satellite channel frequency for this ground-based data; to continue tomorrow;
https://github.com/wmo-im/CCT/wiki/Teleconference.2&3May.2023 notes:
Team decided to add notes, even though it's verbose; Team decided to not rename 'Satellite centre frequency'; Jeff noted that there are some "$"s in the note text.
almost ready for branch; @antoinemerle and @marijanacrepulja will validate.
I have updated the proposal and just double-checked. I suppose it is now ready for branch. @amilan17 could you please create a branch for this issue? Thanks a lot!
Branch is updated.
BUFR examples for validation are included in example.groundBasedMWR.zip example.groundBasedMWR.zip
https://github.com/wmo-im/CCT/wiki/Teleconference.13.July.2023 notes:
@marijanacrepulja will provide samples;
@amilan17 , I have added the notes for this issue. I keep the markup notation for the formula, as e.g. "pandoc" is able to convert this in proper formula for e.g. Word (.docx). But I don't know, how to handle line breaks in the notes.
@SibylleK Branch looks good. I just have a couple questions in the PR #173.
Regarding line breaks -- I can address them when putting together the word/pdf.
Thank you @amilan17. I answered in the PR. And thank you too for the "minor editorial" changes!
@marijanacrepulja I think I'm just waiting for you to validate the samples that Sibylle provided in a comment above.
AachenMWR02_MWR_validated.tar.zip
Hi, @SibylleK and @amilan17
I was able to successfully decode samples provided, using ECMWF software and tables created from the branch. Values look identical. Output of decoding is attached.
@SibylleK I changed 020139 to 020143 due to conflicts.
Thanks @amilan17, it also has to be changed in table D sequence 309072. I updated the FT2023-2 accordingly.
Thanks!
Initial request
DWD is requesting on behalve of E-PROFILE new entries for ground-based microwave radiometer brightness temperature data and derived thermodynomic procfile data.
A microwave radiometer (MWR) is a passive ground based remote sensing instrument exploiting the microwave region of the spectrum to measure vertical profiles of temperature and humidity. There are a few MWR networks worldwide, but data are not exchanged internationally over the GTS and a BUFR sequence for such data does not yet exist. However, EUMETNET is in the process to connect MWRs in Europe to form a network and plans to exchange data over the GTS beginning of 2024. The purpose of this document is to define two BUFR sequences for the exchange of Level 1 (brightness temperatures) and level 2 (meteorological products) data.
Experts from E-PROFILE and the COST action PROBE have jointly elaborated this proposal.
We propose creating the following new BUFR sequences: • 3 09 072 Ground based microwave radiometer brightness temperature observations (Lv1) • 3 09 073 Ground based microwave radiometer retrieval products (Lv2) • 3 03 100 Forecast indexes The new sequences will require the following new BUFR descriptors: • 0 12 190 Brightness temperature error covariance • 0 03 031 Channel bandwidth, full width half maximum (FWHM) • 0 03 032 Channel centre frequency • 0 03 033 Channel band width • 0 03 034 Channel wavelength • 0 13 165 CAPE (convective available potential energy) • 0 13 166 Total totals index • 0 13 167 S index (STT) • 0 13 168 Fog threat index • 0 13 169 MDPI (microburst day potential index) • 0 13 170 TQ index • 0 13 171 CIN (convective inhibition) The new sequences will require the following new code/flag table: • 0 20 143 ~139~ Liquid cloud flag The new sequences will require extending the following existing code table: • 0 02 006 Upper Air Remote Sensing Instrument Type
In addition the new sequences will require extending common code table C-13 (see wmo-im/CCT#132)
Amendment details
Add new entries to BUFR table B:
Notes: (11) The convective available potential energy (CAPE) defines the maximum energy available to an ascending air parcel. CAPE is also referred to as positive buoyancy.
(12) The total totals (TT) index is defined by the combination of the vertical totals ($VT = T{850}*T{500}$) and the cross totals ($CT = Td{850} - T{500}$), resulting in $TT = T{850} + Td{850} - 2 * T_{500}$.
(13) The S index (STT) is defined as $STT = TT - (T{700} + Td{700}) - A$, where TT indicates total totals index and A depends on the vertical totals ($VT = T{850}*T{500}$) such that it penalizes cases with low values of VT (i.e. low vertical temperature gradients): $A = 0 (if\ VT > 25); 2 (if\ 22 <= VT <= 25); 6 (if\ VT < 22)$.
(14) The fog threat (FT) index indicates the potential for radiation fog and is based on the definition of fog point (FP), which is the temperature at which radiation fog will form. The fog point is determined by following the saturation mixing ratio line from the dew point curve at the lifting condensation level (LCL) to the surface temperature. Then, the fog threat is given by the difference of the wet bulb potential temperature at 850 mb ($\theta{WB850}$) and the fog point: $FT = \theta{WB850} - FP$ The potential for radiation fog is low for FT>3, while it becomes high for FT<0.
(15) The microburst day potential index (MDPI) is based on the vertical profiles of equivalent potential temperature and is defined follows: $MDPI = (Max \theta e - Min \theta e_{aloft})/ CT$
MDPI was designed to determine likely and unlikely environments for downbursts. For MDPI values greater than or equal to 1, microbursts are likely.
(16) The TQ index (TQ) is used to assess the potential for lowtopped convection. It is defined as $TQ = (T{850} + Td{850}) - 1.7 * (T_{700})$
(17) The convective inhibition (CIN) indicates the amount of energy required to overcome the negatively buoyant energy the environment exerts on an air parcel. Conceptually, CIN is the opposite of CAPE and is also referred to as negative buoyancy.
Add new entires in existing code table:
Add new code table 020143 ~020139~ - Liquid cloud
Add new sequence to BUFR table D, category 3 - Meteorological sequences common to vertical soundings data
Sequence 3 03 100 - Forecast indices (see Note 4)
Notes: (4) For a discussion of "Forecast indices from ground-based microwave radiometers for operational meteorology" see: https://doi.org/10.5194/amt-8-315-2015
Add new sequence to BUFR table D, category 9 - Vertical sounding sequences (conventional data)
Sequence 3 09 072 - Ground-based microwave radiometer brightness temperature observations (Lv 1)
Sequence 3 09 073 - Ground based microwave radiometer retrieval products (Lv2)
Comments
No response
Requestor(s)
Alexander Häfele (E-PROFILE, MeteoSwiss) Moritz Löffler (E-PROFILE, DWD) Sibylle Krebber (DWD)
Stakeholder(s)
E-PROFILE
Publication(s)
Manual on Codes (WMO-No. 306), Volume I.2
Expected impact of change
MEDIUM
Collaborators
E-PROFILE COST action PROBE
References
A discussion of the forecast indices from ground-based microwave radiometers for operational meteorology can be found here: https://doi.org/10.5194/amt-8-315-2015
Validation
No response