Parameterization of the snow-covered surface albedo in the Noah-MP Version 1.0 by implementing vegetation effects

Park, Sojung; Park, Seon Ki

doi:https://doi.org/10.5194/gmd-9-1073-2016

Articles | Volume 9, issue 3

https://doi.org/10.5194/gmd-9-1073-2016

© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.

https://doi.org/10.5194/gmd-9-1073-2016

© Author(s) 2016. This work is distributed under
the Creative Commons Attribution 3.0 License.

Articles | Volume 9, issue 3

Development and technical paper

|

17 Mar 2016

Development and technical paper |

| 17 Mar 2016

Parameterization of the snow-covered surface albedo in the Noah-MP Version 1.0 by implementing vegetation effects

Sojung Park and Seon Ki Park

Download

Final revised paper (published on 17 Mar 2016)
Preprint (discussion started on 13 Apr 2015)

Interactive discussion

Status: closed

AC: Author comment | RC: Referee comment | SC: Short comment | EC: Editor comment

- Printer-friendly version

- Supplement

RC C548: 'review', Anonymous Referee #1, 25 Apr 2015
- AC C993: 'Reply to the Anonymous Referee #1', Seon Ki Park, 07 Jun 2015
RC C719: 'Review of "Representation of vegetation effects on the snow-covered albedo in the Noah land surface model with multiple physics options"', Richard L.H. Essery, 12 May 2015
- AC C1037: 'Reply to the comments by Richard L. H. Essery', Seon Ki Park, 08 Jun 2015
SC C952: 'Executive Editor Comment on "Representation of vegetation effects on the snow-covered albedo in the Noah land surface model with multiple physics options"', Astrid Kerkweg, 03 Jun 2015
- AC C992: 'Reply to the Exec Editor Comment', Seon Ki Park, 06 Jun 2015

Peer-review completion

AR: Author's response | RR: Referee report | ED: Editor decision

AR by Seon Ki Park on behalf of the Authors (11 Aug 2015) Author's response Manuscript

ED: Referee Nomination & Report Request started (20 Aug 2015) by Jeremy Fyke

RR by Richard L.H. Essery (09 Sep 2015)

ED: Reconsider after major revisions (18 Sep 2015) by Jeremy Fyke

AR by Seon Ki Park on behalf of the Authors (27 Nov 2015) Author's response Manuscript

ED: Referee Nomination & Report Request started (08 Dec 2015) by Jeremy Fyke

RR by Richard L.H. Essery (18 Dec 2015)

Suggestions for revision or reasons for rejection

This paper has been improved by the latest revisions, but some corrections are still required.

24
It is not a simple case that grass, which can bend, will be exposed when snow depth is less than the height of the grass. Because grass is not further considered in this paper, the sentences about grass could simply be deleted and replaced with a note that short vegetation with snow cover generally has a higher albedo than forests.

41-43
Essery (2013) does not state that “many land surface models (LSMs) do not consider the vegetation effect on snow albedo ... resulting in no significant differences in snow-covered albedo”. Qu and Hall (2007) only identified 4 out of 18 CMIP3 models as being of this type.

60
The presented parametrization is simple and effective, but I state again that it cannot be said to be “based on an advanced conceptual frame through a clear understanding of vegetation effects on snow albedo”; this clause should be deleted.

99
MODIS is installed on both TERRA and AQUA; data from both satellites are used to produce the MCD43C3 albedo product, but it is not “installed”.

250
Satellite retrievals of LAI can be unreliable due to snow cover and low solar elevation angles in winter. A better source for LAI would be Lawrence and Chase (2007, doi:10.1029/2006JG000168), which also imposes minimum SAI values. A paper on “Investigating the spread of surface albedo in snow covered forests in CMIP5 models” that I believe has been accepted for publication in Journal of Geophysical Research but has not yet appeared would also be an important reference for this paper; a preprint could be obtained from the author http://www.ec.gc.ca/scitech/default.asp?lang=En&n=F97AE834-1&xsl=scitechprofile&formid=AC5BEAED-CB63-4502-B938-BC03FE2C3423

280
Snow does not necessarily melt earlier in forests; see Lundquist et al. (2013, doi:10.1002/wrcr.20504)

Minor corrections:

29
“Although the tree tops can be covered by snow”

40
“Although the spatial distribution of albedo”

53
“too low compared to observations synthesized by Asner et al. (2003)”

54
“Photosynthetically active leaves and stems being absent in winter”

69
“verified for global river basins”

72
“as the option for snow surface albedo”

81
“performed north of 40N”

82
Delete “with a spin up time of 6 months” – repeated in the next sentence.

87
“Atmospheric data are required”

115
“two similar types of vegetation”

122 and elsewhere
Do not abbreviate “versus”

158
“for all forest types during winter”

173
“how albedo responds to stems”

178
“we have assumed fresh snow”

259
“70% on average”

272
“albedo is therefore greatly overestimated”

276
“in forest regions”

Hide

ED: Reconsider after major revisions (06 Jan 2016) by Jeremy Fyke

AR by Seon Ki Park on behalf of the Authors (25 Jan 2016) Author's response Manuscript

ED: Referee Nomination & Report Request started (28 Jan 2016) by Jeremy Fyke

RR by Anonymous Referee #2 (15 Feb 2016)

ED: Publish as is (03 Mar 2016) by Jeremy Fyke

AR by Seon Ki Park on behalf of the Authors (06 Mar 2016)

Short summary

Snow albedo varies with snow grain size, snow cover thickness, etc. It also depends on the spatial characteristics of land cover and on the canopy density and structure. The Noah-MP model shows a bias error of albedo in winter due to no proper reflection of the vegetation effect. We developed new parameters, called leaf index and stem index, which reflect the vegetation effect on winter albedo. The Noah-MP's performance in albedo has prominently improved with about 69 % decrease in the RMSE.