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Angular Distribution Models (ADMs)

CERES Terra/Aqua Edition4 ADMs

Shortwave ADM Types | |

SW clear ocean

ADM Type Definition Comments
Std < 0.05 Std ≥ 0.05 Std is the standard deviation of clear ocean anisotropic factors in angular bins adjacent to the observation angle  
0600Clear mostly water+land/desert/snowSome with AOD retrieval
1601Clear water; wind speed = 0-2 m/sIn glint, no AOD retrieval
2602Clear water; wind speed = 2-4 m/sIn glint, no AOD retrieval
3603Clear water; wind speed = 4-6 m/sIn glint, no AOD retrieval
4604Clear water; wind speed = 6-8 m/sIn glint, no AOD retrieval
5605Clear water; wind speed = 8-10 m/sIn glint, no AOD retrieval
6606Clear water; wind speed ≥ 10 m/sIn glint, no AOD retrieval
7607Clear water; wind speed = 0-2 m/s; coarse mode aerosols 0-33% AOD binCoarse mode low AOD
8608Clear water; wind speed = 2-4 m/s; coarse mode aerosols 0-33% AOD binCoarse mode low AOD
9609Clear water; wind speed = 4-6 m/s; coarse mode aerosols 0-33% AOD binCoarse mode low AOD
10610Clear water; wind speed = 6-8 m/s; coarse mode aerosols 0-33% AOD binCoarse mode low AOD
11611Clear water; wind speed = 8-10 m/s; coarse mode aerosols 0-33% AOD binCoarse mode low AOD
12612Clear water; wind speed ≥ 10 m/s; coarse mode aerosols 0-33% AOD binCoarse mode low AOD
13613Clear water; wind speed = 0-2 m/s; coarse mode aerosols 33-66% AOD binCoarse mode med AOD
14614Clear water; wind speed = 2-4 m/s; coarse mode aerosols 33-66% AOD binCoarse mode med AOD
15615Clear water; wind speed = 4-6 m/s; coarse mode aerosols 33-66% AOD binCoarse mode med AOD
16616Clear water; wind speed = 6-8 m/s; coarse mode aerosols 33-66% AOD binCoarse mode med AOD
17617Clear water; wind speed = 8-10 m/s; coarse mode aerosols 33-66% AOD binCoarse mode med AOD
18618Clear water; wind speed ≥ 10 m/s; coarse mode aerosols 33-66% AOD binCoarse mode med AOD
19619Clear water; wind speed = 0-2 m/s; coarse mode aerosols 66-100% AOD binCoarse mode high AOD
20620Clear water; wind speed = 2-4 m/s; coarse mode aerosols 66-100% AOD binCoarse mode high AOD
21621Clear water; wind speed = 4-6 m/s; coarse mode aerosols 66-100% AOD binCoarse mode high AOD
22622Clear water; wind speed = 6-8 m/s; coarse mode aerosols 66-100% AOD binCoarse mode high AOD
23623Clear water; wind speed = 8-10 m/s; coarse mode aerosols 66-100% AOD binCoarse mode high AOD
24624Clear water; wind speed ≥ 10 m/s; coarse mode aerosols 66-100% AOD binCoarse mode high AOD
25625Clear water; wind speed = 0-2 m/s; fine mode aerosols 0-33% AOD binFine mode low AOD
26626Clear water; wind speed = 2-4 m/s; fine mode aerosols 0-33% AOD binFine mode low AOD
27627Clear water; wind speed = 4-6 m/s; fine mode aerosols 0-33% AOD binFine mode low AOD
28628Clear water; wind speed = 6-8 m/s; fine mode aerosols 0-33% AOD binFine mode low AOD
29629Clear water; wind speed = 8-10 m/s; fine mode aerosols 0-33% AOD binFine mode low AOD
30630Clear water; wind speed ≥ 10 m/s; fine mode aerosols 0-33% AOD binFine mode low AOD
31631Clear water; wind speed = 0-2 m/s; fine mode aerosols 33-66% AOD binFine mode medium AOD
32632Clear water; wind speed = 2-4 m/s; fine mode aerosols 33-66% AOD binFine mode medium AOD
33633Clear water; wind speed = 4-6 m/s; fine mode aerosols 33-66% AOD binFine mode medium AOD
34634Clear water; wind speed = 6-8 m/s; fine mode aerosols 33-66% AOD binFine mode medium AOD
35635Clear water; wind speed = 8-10 m/s; fine mode aerosols 33-66% AOD binFine mode medium AOD
36636Clear water; wind speed ≥ 10 m/s; fine mode aerosols 33-66% AOD binFine mode medium AOD
37637Clear water; wind speed = 0-2 m/s; fine mode aerosols 66-100% AOD binFine mode high AOD
38638Clear water; wind speed = 2-4 m/s; fine mode aerosols 66-100% AOD binFine mode high AOD
39639Clear water; wind speed = 4-6 m/s; fine mode aerosols 66-100% AOD binFine mode high AOD
40640Clear water; wind speed = 6-8 m/s; fine mode aerosols 66-100% AOD binFine mode high AOD
41641Clear water; wind speed = 8-10 m/s; fine mode aerosols 66-100% AOD binFine mode high AOD
42642Clear water; wind speed ≥ 10 m/s; fine mode aerosols 66-100% AOD binFine mode high AOD
43643Clear water; wind speed = 0-2 m/s; glint aerosols 0-33% AOD binLow ADO bin in glint
44644Clear water; wind speed = 2-4 m/s; glint aerosols 0-33% AOD binLow ADO bin in glint
45645Clear water; wind speed = 4-6 m/s; glint aerosols 0-33% AOD binLow ADO bin in glint
46646Clear water; wind speed = 6-8 m/s; glint aerosols 0-33% AOD binLow ADO bin in glint
47647Clear water; wind speed = 8-10 m/s; glint aerosols 0-33% AOD binLow ADO bin in glint
48648Clear water; wind speed ≥ 10 m/s; glint aerosols 0-33% AOD binLow ADO bin in glint
49649Clear water; wind speed = 0-2 m/s; glint aerosols 33-66% AOD binMedium ADO bin in glint
50650Clear water; wind speed = 2-4 m/s; glint aerosols 33-66% AOD binMedium ADO bin in glint
51651Clear water; wind speed = 4-6 m/s; glint aerosols 33-66% AOD binMedium ADO bin in glint
52652Clear water; wind speed = 6-8 m/s; glint aerosols 33-66% AOD binMedium ADO bin in glint
53653Clear water; wind speed = 8-10 m/s; glint aerosols 33-66% AOD binMedium ADO bin in glint
54654Clear water; wind speed ≥ 10 m/s; glint aerosols 33-66% AOD binMedium ADO bin in glint
55655Clear water; wind speed = 0-2 m/s; glint aerosols 66-100% AOD binHigh ADO bin in glint
56656Clear water; wind speed = 2-4 m/s; glint aerosols 66-100% AOD binHigh ADO bin in glint
57657Clear water; wind speed = 4-6 m/s; glint aerosols 66-100% AOD binHigh ADO bin in glint
58658Clear water; wind speed = 6-8 m/s; glint aerosols 66-100% AOD binHigh ADO bin in glint
59659Clear water; wind speed = 8-10 m/s; glint aerosols 66-100% AOD binHigh ADO bin in glint
60660Clear water; wind speed ≥ 10 m/s; glint aerosols 66-100% AOD binHigh ADO bin in glint

SW cloudy ocean

Non-glint Glint Definition Comments
80680Clouds over ocean; 1.00 < phase ≤ 1.01Liquid
81681Clouds over ocean; 1.01 < phase ≤ 1.75Mixed
82682Clouds over ocean; phase > 1.75Ice
99699Cloudy mostly water + land/desert/snow 

SW Land/Desert

ADM Type Definition Comments
100Clear mostly land/desert + water/snow 
101Clear land/desert: RossLi fit from own 1° by 1° region 
102Clear land/desert: RossLi fit from neighboring 1° by 1° region 
103Clear land/desert: CERES/TRMM ADMs 
150Clouds over land/desert; 1.00 < phase ≤ 1.01liquid
151Clouds over land/desert; 1.01 < phase ≤ 1.75mixed
152Clouds over land/desert; phase > 1.75ice
199Cloudy mostly land/desert + water/snow799 for glint FOV
200Clear mostly snow/ice +water/land/desert800 for glint FOV

SW Sea Ice

ADM type Definition Sunglint default Comments
Cloud fraction Sea ice       * SIBI = Sea Ice Brightness Index
10010% ≤ Cloud fraction ≤ 1% Sea Ice fraction ≤ 1%1601 
1002 1% < Sea Ice fraction ≤ 25%1602 
100325% < Sea Ice fraction ≤ 50%1603 
100450% < Sea Ice fraction ≤ 75%1604 
100575% < Sea Ice fraction ≤ 99%1605 
100699% ≤ Sea Ice fraction, SIBI ≤ 0.851606 
100799% ≤ Sea Ice fraction, 0.85 < SIBI ≤ 0.9351607 
100899% ≤ Sea Ice fraction, SIBI > 0.9351608 
10091% < Cloud Fraction ≤ 25% Sea Ice fraction ≤ 1%1609 
1010 1% < Sea Ice fraction ≤ 25%1610 
101125% < Sea Ice fraction ≤ 50%1611 
101250% < Sea Ice fraction ≤ 75%1612 
101375% < Sea Ice fraction < 99%1613 
101499% ≤ Sea Ice fraction, SIBI ≤ 0.85 1614 
101599% ≤ Sea Ice fraction, 0.85 < SIBI ≤ 0.9351615 
101699% ≤ Sea Ice fraction, SIBI > 0.9351616 
101725% < Cloud Fraction ≤ 50% Sea Ice fraction ≤ 1%1617 
1018 1% < Sea Ice fraction ≤ 25%1618 
101925% < Sea Ice fraction ≤ 50%1619 
102050% < Sea Ice fraction ≤ 75%1620 
102175% < Sea Ice fraction < 99%1621 
102299% ≤ Sea Ice fraction, SIBI ≤ 0.85 1622 
102399% ≤ Sea Ice fraction, 0.85 < SIBI ≤ 0.9351623 
102499% ≤ Sea Ice fraction, SIBI > 0.9351624 
102550% < Cloud Fraction ≤ 75% Sea Ice fraction ≤ 1%1625 
1026 1% < Sea Ice fraction ≤ 25%1626 
102725% < Sea Ice fraction ≤ 50%1627 
102850% < Sea Ice fraction ≤ 75%1628 
102975% < Sea Ice fraction < 99%1629 
103099% ≤ Sea Ice fraction, SIBI ≤ 0.85 1630 
103199% ≤ Sea Ice fraction, 0.85 < SIBI ≤ 0.9351631 
103299% ≤ Sea Ice fraction, SIBI > 0.9351632 
1033 75% < CF < 99%, ln(tau) < 1

* CF = cloud fraction
   tau = cloud optical depth

Sea Ice fraction ≤ 1%1633 
1034 1% < Sea Ice fraction ≤ 25%1634 
103525% < Sea Ice fraction ≤ 50%1635 
103650% < Sea Ice fraction ≤ 75%1636 
103775% < Sea Ice fraction < 99%1637 
103899% ≤ Sea Ice fraction, SIBI ≤ 0.851638 
103999% ≤ Sea Ice fraction, 0.85 < SIBI ≤ 0.9351639 
104099% ≤ Sea Ice fraction, SIBI > 0.9351640 
104175% < CF < 99%, ln(tau) ≥ 1 Sea Ice fraction ≤ 1%1641 
1042 1% < Sea Ice fraction ≤ 25%1642 
104325% < Sea Ice fraction ≤ 50%1643 
104450% < Sea Ice fraction ≤ 75%1644 
104575% < Sea Ice fraction < 99%1645 
104699% ≤ Sea Ice fraction, SIBI ≤ 0.851646 
104799% ≤ Sea Ice fraction, 0.85 < SIBI ≤ 0.9351647 
104899% ≤ Sea Ice fraction, SIBI > 0.9351648 
1049CF ≥ 99%, phase < 1.5,
linear function of ln(tau)
0.0 < SIBI ≤ 0.61649 
10500.6 < SIBI ≤ 0.71650 
10510.7 < SIBI ≤ 0.81651 
10520.8 < SIBI ≤ 0.91652 
10530.9 < SIBI1653 
1054CF ≥ 99%, phase ≥ 1.5,
linear function of ln(tau)
0.0 < SIBI < 0.61654 
10550.6 < SIBI ≤ 0.71655 
10560.7 < SIBI ≤ 0.81656 
10570.8 < SIBI ≤ 0.91657 
10580.9 < SIBI1658 

Fresh Snow

ADM type Cloud fraction Fresh Snow fraction Comments
1201  Average over all scenes
1202 CF ≥ 99%, dark surface, ln(tau) ≤ 10  
120375% ≤ CF < 99%0% < snow fraction ≤ 1% 
120450% ≤ CF < 75%0% < snow fraction ≤ 1% 
120525% ≤ CF < 50%0% < snow fraction ≤ 1% 
1206 1% ≤ CF < 25%0% < snow fraction ≤ 1% 
1208 CF ≥ 99%, bright surface, ln(tau) ≤ 10  
120975% ≤ CF < 99%1% < snow fraction ≤ 25% 
121050% ≤ CF < 75%1% < snow fraction ≤ 25% 
121125% ≤ CF < 50%1% < snow fraction ≤ 25% 
1212 1% ≤ CF < 25%1% < snow fraction ≤ 25% 
1214 CF ≥ 99%, dark surface, ln(tau) > 10  
121575% ≤ CF < 99% Not used in production
121650% ≤ CF < 75%25% < snow fraction ≤ 50% 
121725% ≤ CF < 50%25% < snow fraction ≤ 50% 
1218 1% ≤ CF < 25%25% < snow fraction ≤ 50% 
1220 CF ≥ 99%, bright surface, ln(tau) > 10  
122175% ≤ CF < 99% Not used in production
122250% ≤ CF < 75% Not used in production
122325% ≤ CF < 50%50% < snow fraction ≤ 75% 
1224 1% ≤ CF < 25%50% < snow fraction ≤ 75% 
1230 1% ≤ CF < 25%75% < snow fraction ≤ 99% 
1291Clear-sky freshsnow: RossLi from own 1° by 1° region  
1292Clear-sky freshsnow: RossLi from neighbor 1° by 1° region  
1293Clear-sky freshsnow: CERES TRMM/ADM  

Permanent Snow

ADM type Cloud fraction Comments
1301CF ≥ 99.9%, cld_phase ≤ 1.5, ln(tau) < 1Not used in production
1302CF ≥ 99.9%, cld_phase ≤ 1.5, 1 ≤ ln(tau) < 2 
1303CF ≥ 99.9%, cld_phase ≤ 1.5, 2 ≤ ln(tau) < 3 
1304CF ≥ 99.9%, cld_phase ≤ 1.5, 3 ≤ ln(tau) 
1305CF ≥ 99.9%, cld_phase > 1.5, ln(tau) < 1 
1306CF ≥ 99.9%, cld_phase > 1.5, 1 ≤ ln(tau) < 2 
1307CF ≥ 99.9%, cld_phase > 1.5, 2 ≤ ln(tau) < 3 
1308CF ≥ 99.9%, cld_phase > 1.5, 3 ≤ ln(tau) 
13100.1% < CF ≤ 25% 
131125% < CF ≤ 50% 
131250% < CF ≤ 75% 
131375% < CF < 99.9% 
1315CF ≤ 0.1% Greenland, non-Antarctic permanent snow 
1316 – 1599CF ≤ 0.1% Antarctica, sastrugi ADMs. 

Longwave anisotropy number

ADM TypeDefinitionComments
1Clear ocean Discrete intervals of precipitable water (4), vertical temperature difference (4), surface temperature (10)
50Cloudy ocean Continuous functions of LW parameterization for discrete intervals of precipitable water (4), cloud fraction (5), surface-cloud temperature difference (22), surface temperature (11)
101Clear forest (IGBP=1-5) Discrete intervals of precipitable water (4), vertical temperature difference (4), surface temperature (10)
102Clear savannas (IGBP=8-9)
103Clear grass/cropland (IGBP=6,10-14)
104Clear dark desert (IGBP=7,18)
105Clear bright desert (IGBP=16)
106Clear mixed surface type
150Cloudy land Continuous functions of LW parameterization for discrete intervals of precipitable water (4), cloud fraction (5), surface-cloud temperature difference (22), surface temperature (11)
151Cloudy desert
201Permanent snow clear dayDiscrete intervals of surface temperature (8)
202Permanent snow cloudy day Continuous functions of LW parameterization for discrete intervals of cloud fraction (5), surface-cloud temperature difference (10), surface temperature (8)
207Permanent snow clear nightDiscrete intervals of surface temperature (6)
208Permanent snow cloudy night Continuous functions of LW parameterization for discrete intervals of cloud fraction (5), surface-cloud temperature difference (10), surface temperature (8)
231Fresh snow clear dayDiscrete intervals of surface temperature (5)
232Fresh snow cloudy day Continuous functions of LW parameterization for discrete intervals of cloud fraction (5), surface-cloud temperature difference (10), surface temperature (8)
237Fresh snow clear nightDiscrete intervals of surface temperature (6)
238Fresh snow cloudy night Continuous functions of LW parameterization for discrete intervals of cloud fraction (5), surface-cloud temperature difference (10), surface temperature (8)
261Sea ice clear dayDiscrete intervals of surface temperature (5)
262Sea ice cloudy day Continuous functions of LW parameterization for discrete intervals of cloud fraction (5), surface-cloud temperature difference (10), surface temperature (8)
267Sea ice clear nightDiscrete intervals of surface temperature (4)
268Sea ice cloudy night Continuous functions of LW parameterization for discrete intervals of cloud fraction (5), surface-cloud temperature difference (10), surface temperature (8)

SW/LW Neural Network anisotropy number

ADM TypeANN SceneIGBP
301Evergreen forests1, 2
302Deciduous forests3, 4 ,5
303Woody shrub6, 8
304Dark desert7, 18
305Bright desert16
306Water body17
307Grass9,10,11
308Cropland, cities12,13,14
309Snow15,19
310Ice20

CERES/Terra SSF Edition2B ADMs

Note: Window ADM Types same as Longwave

SW ADM Types | | | | |

Shortwave ADM Types

ADM Type Definition
0 Clear Mostly Water + Land/Desert/Snow
1 – 6 Clear Water
50 – 52 Clouds Over Water
99 Cloudy Mostly Water + Land/Desert/Snow
100 Clear Mostly Land/Desert + Water/Snow
101 – 149 Clear Land/Desert
150 – 198 Clouds over Land/Desert
199 Cloudy Mostly Land/Desert + Water/Snow
200 Clear Mostly Snow + Water/Land/Desert
201 – 298 Clear Snow and Cloudy
299 Cloudy Mostly Snow + Water/Land/Desert
301 – 310 Neural Networks
400 – 499 Ocean Glint: 400 + non-glint Ocean ADM Type
600 – 699 Sea Ice Glint: 400 + non-glint Sea Ice ADM Type

Shortwave Ocean

ADM Type Definition Sunglint Default Comments
0 Clear Mostly Water + Land/Desert/Snow 400  
1 Clear Water; Wind Speed = 0 – 2 m/s 401  
2 Clear Water; Wind Speed = 2 – 4 m/s 402  
3 Clear Water; Wind Speed = 4 – 6 m/s 403  
4 Clear Water; Wind Speed = 6 – 8 m/s 404  
5 Clear Water; Wind Speed = 8 – 10 m/s 405  
6 Clear Water; Wind Speed > 12 m/s 406  
       
50 Clouds Over Ocean; 1.00 < Phase ≤ 1.01 450  Continuous in ln(CF exp(ln(Tau)))
51 Clouds Over Ocean; 1.01 < Phase ≤ 1.75 451  Continuous in ln(CF exp(ln(Tau)))
52 Clouds Over Ocean; Phase > 1.75 452  Continuous in ln(CF exp(ln(Tau)))
       
99 Cloudy Mostly Water + Land/Desert/Snow 499  

Shortwave Land/Desert

ADM Type Definition Comments
100 Clear Mostly Land/Desert + Water/Snow  
101 Clear Land/Desert: 1° fit from within 1° region  
102 Clear Land/Desert: 1° fit from Neighboring region  
103 Clear Land/Desert: CERES/TRMM ADMs  
   
150 Clouds Over Land/Desert; 1.00 < Phase ≤ 1.01  Continuous in ln(CF exp(ln(Tau)))
151 Clouds Over Land/Desert; 1.01 < Phase ≤ 1.75  Continuous in ln(CF exp(ln(Tau)))
152 Clouds Over Land/Desert; Phase > 1.75  Continuous in ln(CF exp(ln(Tau)))
   
199 Cloudy Mostly Land/Desert + Water/Snow  

Shortwave Snow + Sea Ice

ADM Type Definition Sunglint Default Comments
200 Clear Mostly Snow/Sea Ice + Water/Land/Desert 600  
201  Average of all permanent snow scenes    not used in production
202  Permanent snow clear-sky with bright surface    
203  Permanent snow clear-sky with dark surface    
204  Permanent snow; 75% < Clear Area ≤ 99.9%    
205  Permanent snow; 50% < Clear Area ≤ 75%    
206  Permanent snow; 25% < Clear Area ≤ 50%    
207  Permanent snow; 0.1% < Clear Area ≤ 25%    
208  Permanent snow; Thin overcast (tau ≤ 10) over dark snow    
209  Permanent snow; Thin overcast (tau ≤ 10) over bright snow    
210  Permanent snow; Thick overcast (tau > 10) over dark snow    
211  Permanent snow; Thick overcast (tau > 10) over bright snow    
    
220  Average of all Fresh snow scenes    not used in production
221  Fresh snow; Thin povercast (tau < 10) over dark snow    
222  Fresh snow; 1% < Clear Area ≤ 25%
 Snow cover in clear part ≤ 1%
   
223  Fresh snow; 25% < Clear Area ≤ 50%
 Snow cover in clear part ≤ 1%
   
224  Fresh snow; 50% < Clear Area ≤ 75%
 Snow cover in clear part ≤ 1%
   
225  Fresh snow; 75% < Clear Area ≤ 99%
 Snow cover in clear part ≤ 1%
   
226  Fresh snow; Clear Area > 99%
 Snow cover in clear part ≤ 1%
   
227  Fresh snow; Thin overcast (tau < 10) over bright snow    
228  Fresh snow; 1% < Clear Area ≤ 25%
 1% < Snow cover in clear part ≤ 25%
   
229  Fresh snow; 25% < Clear Area ≤ 50%
 1% < Snow cover in clear part ≤ 25%
   
230  Fresh snow; 50% < Clear Area ≤ 75%
 1% < Snow cover in clear part ≤ 25%
   
231  Fresh snow; 75% < Clear Area ≤ 99%
 1% < Snow cover in clear part ≤ 25%
   
232  Fresh snow; Clear Area > 99%
 1% < Snow cover in clear part ≤ 25%
   
233  Fresh snow; Thick overcast (tau > 10) over dark snow    
235  Fresh snow; 25% < Clear Area ≤ 50%
 25% < Snow cover in clear part ≤ 50%
   
236  Fresh snow; 50% < Clear Area ≤ 75%
 25% < Snow cover in clear part ≤ 50%
   
237  Fresh snow; 75% < Clear Area ≤ 99%
 25% < Snow cover in clear part ≤ 50%
   
238  Fresh snow; Clear Area > 99%
 25% < Snow cover in clear part ≤ 50%
   
239  Fresh snow; Thick overcast (tau > 10) over bright snow    
242  Fresh snow; 50% < Clear Area ≤ 75%
 50% < Snow cover in clear part ≤ 75%
   
243  Fresh snow; 75% < Clear Area ≤ 99%
 50% < Snow cover in clear part ≤ 75%
   
244  Fresh snow; Clear Area > 99%
 50% < Snow cover in clear part ≤ 75%
   
249  Fresh snow; 75% < Clear Area ≤ 99%
 75% < Snow cover in clear part ≤ 99%
   
250  Fresh snow; Clear Area > 99%
 75% < Snow cover in clear part ≤ 99%
   
255  Fresh snow; Clear-sky dark snow    
256  Fresh snow; Clear-sky bright snow    
    
260  Average of all Sea Ice scenes    not used in production
261  Sea ice; thin overcast (tau < 10) over dark snow    
262  Sea ice; 1% < Clear Area ≤ 25%
 Snow cover in clear part ≤ 1%
662  
263  Sea ice; 25% < Clear Area ≤ 50%
 Snow cover in clear part ≤ 1%
663  
264  Sea ice; 50% < Clear Area ≤ 75%
 Snow cover in clear part ≤ 1%
664  
265  Sea ice; 75% < Clear Area ≤ 99%
 Snow cover in clear part ≤ 1%
665  
266  Sea ice; Clear Area > 99%
 Snow cover in clear part ≤ 1%
666  
267  Sea ice; thin overcast (tau < 10) over bright snow    
268  Sea ice; 1% < Clear Area ≤ 25%
 1% < Snow cover in clear part ≤ 25%
668  
269  Sea ice; 25% < Clear Area ≤ 50%
 1% < Snow cover in clear part ≤ 25%
669  
270  Sea ice; 50% < Clear Area ≤ 75%
 1% < Snow cover in clear part ≤ 25%
670  
271  Sea ice; 75% < Clear Area ≤ 99%
 1% < Snow cover in clear part ≤ 25%
671  
272  Sea ice; Clear Area > 99%
 1% < Snow cover in clear part ≤ 25%
672  
273  Sea ice; thick overcast (tau > 10) over dark snow 673  
275  Sea ice; 25% < Clear Area ≤ 50%
 25% < Snow cover in clear part ≤ 50%
675  
276  Sea ice; 50% < Clear Area ≤ 75%
 25% < Snow cover in clear part ≤ 50%
676  
277  Sea ice; 75% < Clear Area ≤ 99%
 25% < Snow cover in clear part ≤ 50%
677  
278  Sea ice; Clear Area > 99%
 25% < Snow cover in clear part ≤ 50%
678  
279  Sea ice; thick overcast (tau > 10) over bright snow 679  
282  Sea ice; 50% < Clear Area ≤ 75%
 50% < Snow cover in clear part ≤ 75%
682  
283  Sea ice; 75% < Clear Area ≤ 99%
 50% < Snow cover in clear part ≤ 75%
683  
284  Sea ice; Clear Area > 99%
 50% < Snow cover in clear part ≤ 75%
684  
289  Sea ice; 75% < Clear Area ≤ 99%
 75% < Snow cover in clear part ≤ 99%
689  
290  Sea ice; Clear Area > 99%
 75% < Snow cover in clear part ≤ 99%
690  
295  Sea ice; clear-sky dark snow 695  
296  Sea ice; clear-sky bright snow 696  

Shortwave Neural Network

ADM Type ANN Scene IGBP
301  Evegreen Forests 1, 2
302  Deciduous Forests 3, 4, 5
303  Woody Shrubs 6, 8
304  Dark Desert 7, 18
305  Bright Desert 16
306  Water Bodies 17
307  Grass 9, 10, 11
308  Crops, cities 12, 13, 14
309  Snow and Ice 15, 19
310  Sea Ice 20
LW ADM Types Definition
0 UNDEFINED
1 Clear Water
50 Clouds Over Water
101 – 105 Clear Land/Desert
106 Clear Mixed Surface Type
150 – 151 Clouds over Land/Desert
201 – 299 Clear Snow and Cloudy
301 – 310 Neural Network

LW OCEAN

ADM Type DEFINITION COMMENTS
1 Clear-sky Water Discrete intervals of precipitable water (4), vertical temperature difference (4), surface temperature (5)
50 Clouds over Water Discrete intervals of precipitable water (4), surface temperature (11), surface-cloud temperature difference (22); Continuous functions of LW parameterization surface temperature (5)

LW LAND/DESERT

ADM Type DEFINITION COMMENTS
101 Clear-sky Forests
IGBP = 1 – 5
Discrete intervals of precipitable water(4), vertical temperature difference (4), surface temperature (5)
102 Clear-sky Savannas
IGBP = 8 – 9
Discrete intervals of precipitable water(4), vertical temperature difference (4), surface temperature (5)
103 Clear-sky Grasslands/Croplands
IGBP = 6, 10 – 14
Discrete intervals of precipitable water(4), vertical temperature difference (4), surface temperature (5)
104 Clear-sky Dark Desert
IGBP = 7, 18
Discrete intervals of precipitable water(4), vertical temperature difference (4), surface temperature (5)
105 Clear-sky Bright Desert
IGBP = 16
Discrete intervals of precipitable water(4), vertical temperature difference (4), surface temperature (5)
150 Clouds over Land Discrete intervals of precipitable water(4), surface temperature (11), surface-cloud temperature difference (22); Continuous functions of LW parameterization
151 Clouds over Desert Discrete intervals of precipitable water(4), surface temperature (11), surface-cloud temperature difference (22); Continuous functions of LW parameterization

LW SNOW + SEA ICE

ADM Type DEFINITION COMMENTS
200 Undefined
201 Permanent snow, clear-sky, sfc. temp < 250° K Night-time: sfc. temp < 240° K
202 Permanent snow, 75% < clr. area ≤ 99.9%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp < 20° K
Night-time: sfc. temp < 240° K
203 Permanent snow, 50% < clr. area ≤ 75%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp < 20° K
Night-time: sfc. temp < 240° K
204 Permanent snow, 25% < clr. area ≤ 50%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp < 20° K
Night-time: sfc. temp < 240° K
205 Permanent snow, 0.1% < clr. area ≤ 25%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp < 20° K
Night-time: sfc. temp < 240° K
206 Permanent snow, Overcast;
sfc. temp < 250° K; sfc. temp – cloud eff. temp < 20° K
Night-time: sfc. temp < 240° K
207 Permanent snow, clear-sky, sfc. temp ≥ 250° K Night-time: sfc. temp ≥ 240° K
208 Permanent snow, 75% < clr. area ≤ 99.9%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp < 20° K
Night-time: sfc. temp ≥ 240° K
209 Permanent snow, 50% < clr. area ≤ 75%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp < 20° K
Night-time: sfc. temp ≥ 240° K
210 Permanent snow, 25% < clr. area ≤ 50%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp < 20° K
Night-time: sfc. temp ≥ 240° K
211 Permanent snow, 0.1% < clr. area ≤ 25%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp < 20° K
Night-time: sfc. temp ≥ 240° K
212 Permanent snow, Overcast;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp < 20° K
Night-time: sfc. temp ≥ 240° K
213 Undefined
214 Permanent snow, 75% < clr. area ≤ 99.9%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp ≥ 20° K
Night-time: sfc. temp < 240° K
215 Permanent snow, 50% < clr. area ≤ 75%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp ≥ 20° K
Night-time: sfc. temp < 240° K
216 Permanent snow, 25% < clr. area ≤ 50%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp ≥ 20° K
Night-time: sfc. temp < 240° K
217 Permanent snow, 0.1% < clr. area ≤ 25%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp ≥ 20° K
Night-time: sfc. temp < 240° K
218 Permanent snow, Overcast;
sfc. temp < 250° K; sfc. temp – cloud eff. temp ≥ 20° K
Night-time: sfc. temp < 240° K
219 Undefined
220 Permanent snow, 75% < clr. area ≤ 99.9%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp ≥ 20° K
Night-time: sfc. temp ≥ 240° K
221 Permanent snow, 50% < clr. area ≤ 75%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp ≥ 20° K
Night-time: sfc. temp ≥ 240° K
222 Permanent snow, 25% < clr. area ≤ 50%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp ≥ 20° K
Night-time: sfc. temp ≥ 240° K
223 Permanent snow, 0.1% < clr. area ≤ 25%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp ≥ 20° K
Night-time: sfc. temp ≥ 240° K
224 Permanent snow, Overcast;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp ≥ 20° K
Night-time: sfc. temp ≥ 240° K
225-229 Undefined
230 Undefined
231 Fresh snow, clear-sky, sfc. temp < 250° K
232 Fresh snow, 75% < clr. area ≤ 99.9%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp < 20° K
233 Fresh snow, 50% < clr. area ≤ 75%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp < 20° K
234 Fresh snow, 25% < clr. area ≤ 50%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp < 20° K
235 Fresh snow, 0.1% < clr. area ≤ 25%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp < 20° K
236 Fresh snow, Overcast;
sfc. temp < 250° K; sfc. temp – cloud eff. temp < 20° K
237 Fresh snow, clear-sky, sfc. temp ≥ 250° K
238 Fresh snow, 75% < clr. area ≤ 99.9%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp < 20° K
239 Fresh snow, 50% < clr. area ≤ 75%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp < 20° K
240 Fresh snow, 25% < clr. area ≤ 50%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp < 20° K
241 Fresh snow, 0.1% < clr. area ≤ 25%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp < 20° K
242 Fresh snow, Overcast;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp < 20° K
243 Undefined
244 Fresh snow, 75% < clr. area ≤ 99.9%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp ≥ 20° K
245 Fresh snow, 50% < clr. area ≤ 75%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp ≥ 20° K
246 Fresh snow, 25% < clr. area ≤ 50%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp ≥ 20° K
247 Fresh snow, 0.1% < clr. area ≤ 25%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp ≥ 20° K
248 Fresh snow, Overcast;
sfc. temp < 250° K; sfc. temp – cloud eff. temp ≥ 20° K
249 Undefined
250 Fresh snow, 75% < clr. area ≤ 99.9%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp ≥ 20° K
251 Fresh snow, 50% < clr. area ≤ 75%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp ≥ 20° K
252 Fresh snow, 25% < clr. area ≤ 50%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp ≥ 20° K
253 Fresh snow, 0.1% < clr. area ≤ 25%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp ≥ 20° K
254 Fresh snow, Overcast;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp ≥ 20° K
255-259 Undefined
260 Undefined
261 Sea ice, Clear-sky, sfc. temp < 250° K
262 Sea ice, 75% < clr. area ≤ 99.9%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp < 20° K
263 Sea ice, 50% < clr. area ≤ 75%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp < 20° K
264 Sea ice, 25% < clr. area ≤ 50%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp < 20° K
265 Sea ice, 0.1% < clr. area ≤ 25%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp < 20° K
266 Sea ice, Overcast;
sfc. temp < 250° K; sfc. temp – cloud eff. temp < 20° K
267 Sea ice, Clear-sky, sfc. temp ≥ 250° K
268 Sea ice, 75% < clr. area ≤ 99.9%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp < 20° K
269 Sea ice, 50% < clr. area ≤ 75%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp < 20° K
270 Sea ice, 25% < clr. area ≤ 50%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp < 20° K
271 Sea ice, 0.1% < clr. area ≤ 25%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp < 20° K
272 Sea ice, Overcast;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp < 20° K
273 Undefined
274 Sea ice, 75% < clr. area ≤ 99.9%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp ≥ 20° K
275 Sea ice, 50% < clr. area ≤ 75%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp ≥ 20° K
276 Sea ice, 25% < clr. area ≤ 50%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp ≥ 20° K
277 Sea ice, 0.1% < clr. area ≤ 25%;
sfc. temp < 250° K; sfc. temp – cloud eff. temp ≥ 20° K
278 Sea ice, Overcast;
sfc. temp < 250° K; sfc. temp – cloud eff. temp ≥ 20° K
279 Undefined
280 Sea ice, 75% < clr. area ≤ 99.9%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp ≥ 20° K
281 Sea ice, 50% < clr. area ≤ 75%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp ≥ 20° K
282 Sea ice, 25% < clr. area ≤ 50%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp ≥ 20° K
283 Sea ice, 0.1% < clr. area ≤ 25%;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp ≥ 20° K
284 Sea ice, Overcast;
sfc. temp ≥ 250° K; sfc. temp – cloud eff. temp ≥ 20° K
285-299 Undefined

LW NEURAL NETWORK

ADM Type ANN Scene IGBP
301 Evegreen Forests 1, 2
302 Deciduous Forests 3, 4, 5
303 Woody Shrubs 6, 8
304 Dark Desert 7, 18
305 Bright Desert 16
306 Water Bodies 17
307 Grass 9, 10, 11
308 Crops, cities 12, 13, 14
309 Snow and Ice 15, 19
310 Sea Ice 20
  FORMAT: xxyyz (range: 00001 – 27279)

      xx = layer 1 ID (0 – 27)
      yy = layer 2 ID (0 – 27)
      z = surface type (1 – 9):
          1 = water; 2 = forest; 3 = savannas; 4 = grasslands/croplands;
          5 = open shrubs; 6 = barren desert; 7 = permanent snow; 8 = fresh snow; 9 = sea ice.
  Cloud Layer ID:
        clear-sky FOV: xx = 0; yy = 0
        cloudy single layer: xx = 1 – 27; yy = 0
        cloudy multilayer: xx = 1 – 27; yy = 1 – 27
NOTE: Layer 2 is only defined if the separation between two SSF layers crosses pressure boundaries. Otherwise, merge the two SSF layers into a single layer.
If FOV is cloudy, xx and/or yy are defined by cloud fraction, cloud height and cloud optical depth as follows:
  PCL MCL OVC
HIGH 19 20 21 22 23 24 25 26 27
MIDDLE 10 11 12 13 14 15 16 17 18
LOW 1 2 3 4 5 6 7 8 9
  Thin Mod Thick Thin Mod Thick Thin Mod Thick
Where
  PCL: cld. fraction = 0.1 – 40%
  MCL: cld. fraction = 40 – 99%
  OVC: cld. fraction = 99 – 100%
  HIGH: eff. pressure < 440 mb
  MIDDLE: eff. pressure = 440 – 680 mb
  LOW: eff. pressure > 680 mb
  THIN: tau < 3.35
  MOD: tau = 3.35 – 22.63
  THICK: tau > 22.63


  NOTES:

  – The EFFECTIVE CLOUD PRESSURE is used, not the CLOUD TOP PRESSURE.

  – To decode cloud classification index (icldtype):
            icld1 = int(icldtype/1000)
            icld2 = int(icldtype – icld1*1000)/10
            isfctype = icldtype – icld1*1000 – icld2*10

  – To determine cloud property array indices:
            ipres = int(icldx/9.001) + 1
            icldf = int[ (icldx – (ipres – 1)*9)/3.001] + 1
            itau = int[ (icldx – (ipres – 1)*9 – (icldf – 1)*3)/1.001] + 1

  – From this SSF classification, one could map all possible layer, cloud fraction and tau combinations into a single digit.
      There are a total of 271 possible cloud conditions per surface type:
            1   clear
            27 single layer
            81 multilayer: low + mid
            81 multilayer: low + high
            81 multilayer: mid + high

The CERES/Terra SSF dataset includes about 5% of CERES footprints with missing imager information or insufficient MODIS data for a reliable scene ID. The frequency of occurrence of these fields-of-view depends on imager viewing geometry, geographic location, and on certain cloud conditions, and can reach up to 50% of data locally or for a specific scene type (see validation plots below). In order to avoid any systematic bias in radiative budget data, it is very important to provide accurate TOA flux values for such footprints. This requires ADMs that can be used with the CERES measurements alone.

Motivation:

  • Provide accurate flux values for CERES footprints with excessive “non-retrieval” imager information.
  • ANN technique advantage: highly non-linear multi-dimensional continuous transfer functions.
  • Application of pre-trained ANN-based ADMs to satellite data without complex scene ID over field-of-view.

Reference:

Details on building of training sets, ANN training algorithm and results on reproducing CERES ADMs are available in:

  • K. Loukachine and N.G. Loeb
    Application of an Artificial Neural Network Simulation for Top-of-Atmosphere Radiative Flux Estimation from CERES.
    Journal of Atmospheric and Oceanic Technology, vol. 20, No. 12, p. 1749-1757, 2003 ( PDF file ).
  • K. Loukachine and N.G. Loeb
    Top-of-Atmosphere Flux Retrievals from CERES Using Artificial Neural Networks.
    J. Remote Sensing of Environment , v. 93, No. 3, 381-39, 2004 ( PDF file ).

General ANN structure 5IN-7TS-11TS-1L (SW case)

For our purpose we use partially connected feed-forward error back-propagation multi-layer neural neworks. Generalized Delta rule with variable learning rate and a constant momentum is used as the ANN training algorithm.

General ANN Structure, SW case

    L1, L2 – layers of neurons with sigmoidal activation function;
    L3 – linear output single-neuron layer.
    The first neuron layer is divided into two neuron clusters: scene ID and primary input variables.
    W1, W2, W3 – neuron connection weight matrices;
    N – normalization of the input variables;
    F – fuzzification of the input (for training only).

Generally, ANN algorithm can be divided into three phases:

  • creating representative traning sets;
  • training the ANN;
  • application of ANN to the data of iterest (validation is assumed).

Training sets for Edition-2 CERES/Terra ANN-based ADMs are built on one year (2001) of RAPS and along-track data, both day-time and night-time. The data stratified in the chosen ANN input variables independently, and for every bin the mean ADM value and STD of distribution are calculated using CERES footprints with reliable imager information. The goal is to make ANN reproduce the ADM values over entire training set with minimal error. To avoid noisy configurations, each training set has an upper limit for STD of ADM value within configuration (bin). On the figure below it is illustrated for the SW ocean and dark desert scene types:

Noise Cut, Ocean and Dark Desert scene types

Standard deviation of the training set ADM versus glint angle. Every entry on the plot represents a configuration in the training set. The color scale is number of training configuratrions. Noise cut is shown with a horizontal black line. As it is expected, the noise is cut off uniformly for the land scene types, and mostly at small glint angle for the ocean.

The configurations with STD(ADM) above the limit are exluded from ANN training. As result, they are not considered for flux retrieval. All training sets for all scene types and channels (SW, LW and WN), exept the ocean scene type, consisted from 10,000 to 15,000 training configurations. The ocean (SW, LW, WN) training set consisted of about 25,000 training configurations. The off-limit configurations range from 2% to 5% in case of land scene types, and about 10% in case of ocean scene types (in sun-glint region the original Terra/CERES ADMs become noisy).

Day-Time:

Day-Time SW and LW training set stratification (scene ID group of variables indicated with blue)
      Variable SW N bins SW Bin Width Variable LW N bins LW Bin Width
1 VZA 7 10 VZA 7 10
2 RAZ 9 20 RAZ 6 30
3 LWR 15 10 SWR 20 15
4 SZA 9 10 PW 10 1.0
5 SWR 30 10 LWR 30 5

Training was performed with 10,000 iterations for all ANN scene types and channels (SW, LW and WN). The number of iterations is a compromise between achieving the lowest possible error and computation time. Figure below illustrates training process (right) and the result at the end of training (left) for shorwave Bright Desert ANN scene type. The ANN training errors are defined as mean (bias) and STD of the difference between the training and ANN ADM values over entire set.

ANN Training, Bright Desert scene type

Shortwave Bright Desert scene type ANN training. RIGHT: Decrease of the Error Index with training iterations. LEFT: ANN value of ADM versus training set ADM value. The mean and STD values of the difference between two over a training set are considered as ANN training errors.

Day-Time ANN Scenes and Training Errors:
Index ANN Scene IGBP Types SW Bias (%) SW STD (%) LW Bias (%) LW STD (%)
1 EF 1, 2 0.110 3.419 0.011 0.984
2 DF 3, 4, 5 0.146 3.872 0.007 0.812
3 WS 6, 8 0.128 3.572 0.011 0.909
4 DD 7, 18 0.106 3.499 0.006 0.719
5 BD 16 0.084 2.965 0.008 0.667
6 WB 17 0.129 4.062 0.010 0.913
7 GR 9, 10, 11 0.120 3.481 0.010 0.901
8 CC 12, 13, 14 0.120 3.405 0.009 0.852
9 SN 15, 19 0.118 3.657 0.013 1.022
10 SI 20 0.122 3.826 0.005 0.620

The ANN scene types are defined by using IGBP geomap (see the table above): evergreen forests (EF), decidous forects (DF), shrubs (WS), dark desert (DD), bright desert (BD), water bodies (WB), grass (GR), crops and urban areas (CC), snow-ice land (SN), sea-ice (SI).

When training is successfully finished, ANN provides a very complex 5-dimentional transfer function. Here are examples of 2-dimentional projections in VZA and RAZ for Shortwave ANN dark desert and ocean scene types (fixed variables: LWR = 90 W/m2sr, SWR = 100 W/m2sr, SZA = 10 and 80 deg.)

Night-Time:

Night-Time LW and WN training set stratification (scene ID group of variables indicated with blue)
      Variable LW N bins LW Bin Width Variable WN N bins WN Bin Width
1 VZA 7 10 VZA 7 10
2 RAZ 6 30 RAZ 6 30
3 SZA 9 10 SZA 9 10
4 PW 10 1.0 PW 10 1.0
5 LWR 40 3 WNR 40 1.5
Night-Time ANN Scenes and Training Errors
Index ANN Scene IGBP Types LW Bias (%) LW STD (%) WN Bias (%) WN STD (%)
1 EF 1, 2 0.023 1.479 0.072 2.673
2 DF 3, 4, 5 0.013 1.016 0.032 1.735
3 WS 6, 8 0.028 1.659 0.095 3.032
4 DD 7, 18 0.015 1.087 0.036 1.929
5 BD 16 0.017 1.203 0.039 2.007
6 WB 17 0.010 0.925 0.039 1.950
7 GR 9, 10, 11 0.021 1.370 0.057 2.535
8 CC 12, 13, 14 0.014 1.151 0.042 2.076
9 SN 15, 19 0.012 1.046 0.016 1.331
10 SI 20 0.006 0.830 0.019 1.273

Validation:

The first two weeks of February 2001 CERES/Terra RAPS and along-track data are used for ANN-based ADMs validation. The ANN-derived flux is compared with CERES/Terra Edition-2A empirical ADMs flux.

Validation Plots (All-sky, Terra, February 2001, Edition-1A cloud mask)
  F(ADM) – F(ANN) F(ADM) – F(ANN)
vs Scene Type
F(ADM) – F(ANN)
vs VZA
ANN Fraction
SW plot plot plot map
3.52% (Global RAPS)
5.61% (Global FAPS)
LW Day-Time plot plot plot map
5.19% (Global RAPS)
LW Night-Time plot plot plot map
3.49% (Global RAPS)

Summary:

  • ANN-based CERES/Terra Edition-2 SW, LW and WN channel TOA fluxes have very small mean bias from empirically developped ADMs for all scene types.
  • The instantaneous TOA flux errors for ANN-based ADMs are about factor 1.4 larger for SW, 1.2 for LW night-time, and practically the same for LW day-time. The increase in instantaneous errors is due to lack of imager information.
  • It has been shown by K. Loukachine and N.G. Loeb (JTECH 2003) the ANN technique is more accurate than ERBE ADMs applied to new data.

Shortwave


Longwave


Window

TABLES:
Permanent Snow
Fresh Snow
Sea Ice
TABLES:
Permanent Snow: Day Night
Fresh Snow: Day Night
Sea Ice: Day Night
TABLES:
Permanent Snow: Day Night
Fresh Snow: Day Night
Sea Ice: Day Night

Shortwave Plots

Permanent Snow
SZA Clear-Sky Broken Clouds Overcast
39°    
41°
43°
45°
47°
49°
51°
53°
55°
57°
59°
61°
63°
65°
67°
69°
71°
73°
75°
77°
79°
81°
83°
85°
87°
89°
Fresh Snow
SZA Cloud Fraction (%)
Clear-sky 0.1-25 25-50 50-75 75-99.9
12.5°  
17.5°
22.5°
27.5°
32.5°
37.5°
42.5°
47.5°
52.5°
57.5°
62.5°
67.5°
72.5°
77.5°
82.5°
87.5°
SZA Cloud + Snow = 100% Overcast
12.5°
17.5°
22.5°
27.5°
32.5°
37.5°
42.5°
47.5°
52.5°
57.5°
62.5°
67.5°
72.5°
77.5°
82.5°
87.5°
Sea Ice
SZA Cloud Fraction (%)
Clear-sky 0.1-25 25-50 50-75 75-99.9
32.5°
37.5°
42.5°
47.5°
52.5°
57.5°
62.5°
67.5°
72.5°
77.5°
82.5°
87.5°
SZA Cloud + Ice = 100% Overcast
32.5°
37.5°
42.5°
47.5°
52.5°
57.5°
62.5°
67.5°
72.5°
77.5°
82.5°
87.5°

Cloud-mask snow/ice percent coverage (SSF-69):

This parameter is PSF-weighted percent of snow/ice within the CERES FOV (see CERES SSF Collection Guide, p. 51).

Surface type index (SSF-25):

This is a list of the 8 most prominent surface types within the CERES FOV, which are ordered on area coverage with the largest being first (see CERES SSF Collection Guide, p. 25).

Snow/Ice percent coverage clear-sky overhead-sun vis albedo (SSF-30):

  • Indicates whether or not the CERES FOV centroid falls within the region near coastline where the microwave imager cannot distinguish between land/snow and water/ice.
  • Also provides the overhead sun clear-sky visible albedo from history maps generated by the CERES cloud group.
  FORMAT:  XYYY   where

  X = 0: CERES FOV centroid is in region (away from a coastline) where microwave imager retrievals are available.
  X = 1: CERES FOV centroid is in region (near a coastline) where microwave imager retrievals are unavailable.

  YYY = 0 – 100% or 999 (default)

X is determined by reading 10-minute map that provides a flag to indicate where the microwave imager does not provide a retrieval due to proximity to the coastline.

YYY is the overhead sun clear-sky visible albedo from history maps generated by the CERES cloud group. Default value is 999. To use this new parameter:

    icoast = int(XYYY/1000)
    iadmgeo = XYYY – icoast*1000

CERES/TRMM SSF Edition2B ADMs

Note: Window ADM Types same as Longwave

Downloads: SW ADM Types | LW Day ADM Types | LW Night ADM Types | CERES/TRMM Shortwave ADMs (tar.Z file)

Shortwave ADMs | | | |

Clear-Sky Ocean

Solar Zenith Angle Figures Tables
0°-10°
10°-20°
20°-30°
30°-40°
40°-50°
50°-60°
60°-70°
70°-80°
80°-90°
Clear Ocean Albedo

Liquid Water Clouds Over Ocean

SZA Cloud Fraction (%)
0.1-10 10-20 20-30 30-40 40-50 50-60 60-70 70-80 80-90 90-95 95-99.9 99.9-100
0°-10°
10°-20°
20°-30°
30°-40°
40°-50°
50°-60°
60°-70°
70°-80°
80°-90°

Ice Clouds Over Ocean

SZA Cloud Fraction (%)
0.1-10 10-20 20-30 30-40 40-50 50-60 60-70 70-80 80-90 90-95 95-99.9 99.9-100
0°-10°
10°-20°
20°-30°
30°-40°
40°-50°
50°-60°
60°-70°
70°-80°
80°-90°

Clear-Sky Land and Desert

Solar Zenith Angle Figures Tables
0°-10°
10°-20°
20°-30°
30°-40°
40°-50°
50°-60°
60°-70°
70°-80°
80°-90°

Clear-Sky Land & Desert Albedo

Liquid Water Clouds Over Land with Moderate-to-High Tree/Shrub Coverage

SZA Cloud Fraction (%)
0.1-25 25-50 50-75 75-99.9 99.9-100
0°-10°
10°-20°
20°-30°
30°-40°
40°-50°
50°-60°
60°-70°
70°-80°
80°-90°

Liquid Water Clouds Over Land with Low-to-Moderate Tree/Shrub Coverage

SZA Cloud Fraction (%)
0.1-25 25-50 50-75 75-99.9 99.9-100
0°-10°
10°-20°
20°-30°
30°-40°
40°-50°
50°-60°
60°-70°
70°-80°
80°-90°

Liquid Water Clouds Over Dark Desert

SZA Cloud Fraction (%)
0.1-25 25-50 50-75 75-99.9 99.9-100
0°-10°
10°-20°
20°-30°
30°-40°
40°-50°
50°-60°
60°-70°
70°-80°
80°-90°

Liquid Water Clouds Over Bright Desert

SZA Cloud Fraction (%)
0.1-25 25-50 50-75 75-99.9 99.9-100
0°-10°
10°-20°
20°-30°
30°-40°
40°-50°
50°-60°
60°-70°
70°-80°
80°-90°

Ice Clouds Over Land with Moderate-to-High Tree/Shrub Coverage

SZA Cloud Fraction (%)
0.1-25 25-50 50-75 75-99.9 99.9-100
0°-10°
10°-20°
20°-30°
30°-40°
40°-50°
50°-60°
60°-70°
70°-80°
80°-90°

Ice Clouds Over Land with Low-to-Moderate Tree/Shrub Coverage

SZA Cloud Fraction (%)
0.1-25 25-50 50-75 75-99.9 99.9-100
0°-10°
10°-20°
20°-30°
30°-40°
40°-50°
50°-60°
60°-70°
70°-80°
80°-90°

Ice Clouds Over Dark Desert

SZA Cloud Fraction (%)
0.1-25 25-50 50-75 75-99.9 99.9-100
0°-10°
10°-20°
20°-30°
30°-40°
40°-50°
50°-60°
60°-70°
70°-80°
80°-90°

Ice Clouds Over Bright Desert

SZA Cloud Fraction (%)
0.1-25 25-50 50-75 75-99.9 99.9-100
0°-10°
10°-20°
20°-30°
30°-40°
40°-50°
50°-60°
60°-70°
70°-80°
80°-90°

Clear-Sky Ocean

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Broken Cloud Fields Over Ocean

Precipitable Water
Percentile Intervals
Cloud Fraction (%)
0.1-25 25-50 50-75 75-99.9
< 33
33 – 66
> 66

Overcast Ocean

Precipitable Water
Percentile Intervals
plots tables
< 33 %
33 – 66 %
> 66 %

Clear-Sky Land

/

Clear-Sky Desert

/

Broken Cloud Fields Over Land

Precipitable Water
Percentile Intervals
Cloud Fraction (%)
0.1-25 25-50 50-75 75-99.9
< 33
33 – 66
> 66

Broken Cloud Fields Over Desert

Precipitable Water
Percentile Intervals
Cloud Fraction (%)
0.1-25 25-50 50-75 75-99.9
< 33
33 – 66
> 66

Overcast Land and Desert

Precipitable Water
Percentile Intervals
plots tables
< 33 %
33 – 66 %
> 66 %

Clear-Sky Ocean

/

Broken Cloud Fields Over Ocean

Precipitable Water
Percentile Intervals
Cloud Fraction (%)
0.1-25 25-50 50-75 75-99.9
< 33
33 – 66
> 66

Overcast Ocean

Precipitable Water
Percentile Intervals
plots tables
< 33 %
33 – 66 %
> 66 %

Clear-Sky Land

/

Clear-Sky Desert

/

Broken Cloud Fields Over Land

Precipitable Water
Percentile Intervals
Cloud Fraction (%)
0.1-25 25-50 50-75 75-99.9
< 33
33 – 66
> 66

Broken Cloud Fields Over Desert

Precipitable Water
Percentile Intervals
Cloud Fraction (%)
0.1-25 25-50 50-75 75-99.9
< 33
33 – 66
> 66

Overcast Land and Desert

Precipitable Water
Percentile Intervals
plots tables
< 33 %
33 – 66 %
> 66 %

Clear-Sky Ocean

/

Broken Cloud Fields Over Ocean

Precipitable Water
Percentile Intervals
Cloud Fraction (%)
0.1-25 25-50 50-75 75-99.9
< 33
33 – 66
> 66

Overcast Ocean

Precipitable Water
Percentile Intervals
plots tables
< 33 %
33 – 66 %
> 66 %

Clear-Sky Land

/

Clear-Sky Desert

/

Broken Cloud Fields Over Land

Precipitable Water
Percentile Intervals
Cloud Fraction (%)
0.1-25 25-50 50-75 75-99.9
< 33
33 – 66
> 66

Broken Cloud Fields Over Desert

Precipitable Water
Percentile Intervals
Cloud Fraction (%)
0.1-25 25-50 50-75 75-99.9
< 33
33 – 66
> 66

Overcast Land and Desert

Precipitable Water
Percentile Intervals
plots tables
< 33 %
33 – 66 %
> 66 %

Clear-Sky Ocean

/

Broken Cloud Fields Over Ocean

Precipitable Water
Percentile Intervals
Cloud Fraction (%)
0.1-25 25-50 50-75 75-99.9
< 33
33 – 66
> 66

Overcast Ocean

Precipitable Water
Percentile Intervals
plots tables
< 33 %
33 – 66 %
> 66 %

Clear-Sky Land:

/

Clear-Sky Desert

/

Broken Cloud Fields Over Land

Precipitable Water
Percentile Intervals
Cloud Fraction (%)
0.1-25 25-50 50-75 75-99.9
< 33
33 – 66
> 66

Broken Cloud Fields Over Desert

Precipitable Water
Percentile Intervals
Cloud Fraction (%)
0.1-25 25-50 50-75 75-99.9
< 33
33 – 66
> 66

Overcast Land and Desert

Precipitable Water
Percentile Intervals
plots tables
< 33 %
33 – 66 %
> 66 %

ERBE ADMs

Shortwave (SW) Longwave (LW)
SW ADMs ( ADM Types) LW ADMs ( ADM Types)