# poly fit of the topside / total TEC ratio (alpha) as a function of day-of-year, for Sentinel-1.
# reference: equation (14) in Yunjun et al. (2022, IEEE-TGRS)
# alpha = 3.4302124e+01
#	- 3.4292573e-01 * t_d
#	+ 2.4354539e-03 * t_d**2
#	+ 4.5565852e-05 * t_d**3
#	- 4.7181763e-07 * t_d**4
#	+ 1.4302660e-09 * t_d**5
#	- 1.3914712e-12 * t_d**6
# where t_d is the day of the year
# t_d, topside TEC percentage, sub-orbital TEC percentage
1.0	0.33961678845467846	0.6603832115453215
2.0	0.3362637140785372	0.6637362859214628
3.0	0.3329645833406046	0.6670354166593955
4.0	0.3297218526502342	0.6702781473497659
5.0	0.3265378702827534	0.6734621297172466
6.0	0.3234148780607168	0.6765851219392832
7.0	0.32035501302514213	0.6796449869748579
8.0	0.31736030909672736	0.6826396909032726
9.0	0.31443269872704865	0.6855673012729513
10.0	0.3115740145397404	0.6884259854602597
11.0	0.3087859909616564	0.6912140090383436
12.0	0.30607026584401226	0.6939297341559878
13.0	0.3034283820735097	0.6965716179264902
14.0	0.30086178917344164	0.6991382108265584
15.0	0.29837184489477925	0.7016281551052208
16.0	0.2959598167972399	0.7040401832027601
17.0	0.2936268838203371	0.7063731161796629
18.0	0.29137413784441135	0.7086258621555886
19.0	0.2892025852416424	0.7107974147583576
20.0	0.28711314841704355	0.7128868515829565
21.0	0.2851066673394365	0.7148933326605635
22.0	0.2831839010624082	0.7168160989375918
23.0	0.2813455292352487	0.7186544707647513
24.0	0.2795921536038711	0.720407846396129
25.0	0.27792429950171166	0.7220757004982883
26.0	0.27634241733061293	0.7236575826693871
27.0	0.2748468840316869	0.7251531159683131
28.0	0.2734380045461602	0.7265619954538398
29.0	0.2721160132662006	0.7278839867337994
30.0	0.2708810754757252	0.7291189245242748
31.0	0.2697332887811893	0.7302667112188107
32.0	0.2686726845323574	0.7313273154676426
33.0	0.2676992292330553	0.7323007707669447
34.0	0.2668128259419036	0.7331871740580964
35.0	0.2660133156630328	0.7339866843369671
36.0	0.2653004787267793	0.7346995212732207
37.0	0.26467403616036356	0.7353259638396364
38.0	0.264133651048549	0.735866348951451
39.0	0.2636789298842828	0.7363210701157172
40.0	0.26330942390931766	0.7366905760906823
41.0	0.2630246304448153	0.7369753695551847
42.0	0.2628239942119311	0.737176005788069
43.0	0.2627069086423807	0.7372930913576192
44.0	0.2626727171789873	0.7373272828210127
45.0	0.2627207145662106	0.7372792854337894
46.0	0.2628501481306575	0.7371498518693425
47.0	0.2630602190515737	0.7369397809484264
48.0	0.263350083621317	0.736649916378683
49.0	0.2637188544958122	0.7362811455041878
50.0	0.2641656019349867	0.7358343980650133
51.0	0.2646893550331884	0.7353106449668116
52.0	0.265289102939584	0.7347108970604159
53.0	0.2659637960685401	0.7340362039314599
54.0	0.26671234729998405	0.733287652700016
55.0	0.2675336331697476	0.7324663668302525
56.0	0.26842649504989113	0.7315735049501089
57.0	0.26938974031900964	0.7306102596809904
58.0	0.27042214352252	0.72957785647748
59.0	0.2715224475229297	0.7284775524770704
60.0	0.27268936464008714	0.7273106353599128
61.0	0.2739215777814128	0.7260784222185872
62.0	0.2752177415621125	0.7247822584378876
63.0	0.27657648341537155	0.7234235165846284
64.0	0.2779964046925306	0.7220035953074694
65.0	0.27947608175324284	0.7205239182467571
66.0	0.2810140670456124	0.7189859329543876
67.0	0.2826088901763144	0.7173911098236856
68.0	0.28425905897069653	0.7157409410293034
69.0	0.28596306052286136	0.7140369394771386
70.0	0.2877193622357312	0.7122806377642688
71.0	0.28952641285109304	0.710473587148907
72.0	0.29138264346962583	0.7086173565303742
73.0	0.29328646856090923	0.7067135314390908
74.0	0.2952362869634128	0.7047637130365871
75.0	0.2972304828744676	0.7027695171255324
76.0	0.299267426830219	0.700732573169781
77.0	0.3013454766755601	0.6986545233244399
78.0	0.3034629785240479	0.6965370214759521
79.0	0.3056182677077997	0.6943817322922003
80.0	0.30780966971737145	0.6921903302826286
81.0	0.31003550113161754	0.6899644988683824
82.0	0.3122940705375317	0.6877059294624683
83.0	0.3145836794400698	0.6854163205599302
84.0	0.3169026231619532	0.6830973768380468
85.0	0.3192491917334547	0.6807508082665453
86.0	0.32162167077216464	0.6783783292278354
87.0	0.3240183423527396	0.6759816576472604
88.0	0.32643748586663124	0.6735625141333688
89.0	0.3288773788717979	0.6711226211282021
90.0	0.33133629793239644	0.6686637020676036
91.0	0.33381251944845636	0.6661874805515436
92.0	0.33630432047553455	0.6636956795244655
93.0	0.3388099795343523	0.6611900204656477
94.0	0.3413277774104128	0.6586722225895871
95.0	0.34385599794360083	0.6561440020563991
96.0	0.3463929288077634	0.6536070711922366
97.0	0.34893686228027193	0.651063137719728
98.0	0.35148609600156605	0.648513903998434
99.0	0.3540389337246782	0.6459610662753218
100.0	0.3565936860547403	0.6434063139452597
101.0	0.3591486711784717	0.6408513288215283
102.0	0.361702215583648	0.638297784416352
103.0	0.364252654768552	0.6357473452314479
104.0	0.3667983339414056	0.6332016660585944
105.0	0.36933760870978316	0.6306623912902168
106.0	0.3718688457600067	0.6281311542399932
107.0	0.37439042352652163	0.6256095764734784
108.0	0.37690073285125486	0.6230992671487452
109.0	0.3793981776329536	0.6206018223670464
110.0	0.3818811754665058	0.6181188245334942
111.0	0.3843481582722425	0.6156518417277574
112.0	0.3867975729152204	0.6132024270847796
113.0	0.38922788181448714	0.6107721181855128
114.0	0.39163756354232715	0.6083624364576729
115.0	0.39402511341348917	0.6059748865865109
116.0	0.39638904406439524	0.6036109559356048
117.0	0.3987278860223308	0.6012721139776692
118.0	0.4010401882646169	0.5989598117353832
119.0	0.40332451876776276	0.5966754812322372
120.0	0.40557946504660064	0.5944205349533993
121.0	0.40780363468340197	0.592196365316598
122.0	0.40999565584697406	0.5900043441530259
123.0	0.41215417780173963	0.5878458221982603
124.0	0.41427787140679667	0.5857221285932033
125.0	0.4163654296049596	0.5836345703950404
126.0	0.41841556790178297	0.5815844320982171
127.0	0.4204270248345654	0.5795729751654346
128.0	0.42239856243133544	0.5776014375686646
129.0	0.42432896665981906	0.5756710333401809
130.0	0.42621704786638787	0.5737829521336122
131.0	0.42806164120498946	0.5719383587950105
132.0	0.4298616070560584	0.5701383929439416
133.0	0.4316158314354096	0.5683841685645904
134.0	0.43332322639311216	0.5666767736068878
135.0	0.43498273040234553	0.5650172695976545
136.0	0.43659330873823565	0.5634066912617643
137.0	0.4381539538466744	0.5618460461533257
138.0	0.43966368570311887	0.5603363142968811
139.0	0.4411215521613729	0.5588784478386271
140.0	0.4425266292923494	0.5574733707076506
141.0	0.4438780217128152	0.5561219782871848
142.0	0.4451748629041157	0.5548251370958843
143.0	0.4464163155208821	0.5535836844791179
144.0	0.44760157168972	0.5523984283102801
145.0	0.44872985329787873	0.5512701467021213
146.0	0.44980041227190265	0.5501995877280974
147.0	0.45081253084626355	0.5491874691537364
148.0	0.4517655218219749	0.5482344781780251
149.0	0.4526587288151868	0.5473412711848131
150.0	0.45349152649576296	0.546508473504237
151.0	0.4542633208158389	0.5457366791841611
152.0	0.45497354922836136	0.5450264507716387
153.0	0.4556216808956095	0.5443783191043905
154.0	0.45620721688769694	0.5437927831123031
155.0	0.4567296903710558	0.5432703096289442
156.0	0.4571886667869019	0.5428113332130982
157.0	0.45758374401968155	0.5424162559803185
158.0	0.4579145525554988	0.5420854474445012
159.0	0.45818075563052574	0.5418192443694743
160.0	0.4583820493693929	0.5416179506306071
161.0	0.4585181629135617	0.5414818370864383
162.0	0.45858885853967735	0.5414111414603227
163.0	0.45859393176790525	0.5414060682320947
164.0	0.4585332114602463	0.5414667885397537
165.0	0.45840655990883505	0.541593440091165
166.0	0.4582138729142191	0.5417861270857809
167.0	0.45795507985361994	0.5420449201463801
168.0	0.45763014373917454	0.5423698562608255
169.0	0.4572390612661594	0.5427609387338406
170.0	0.4567818628511946	0.5432181371488054
171.0	0.45625861266043144	0.5437413873395686
172.0	0.4556694086277188	0.5443305913722811
173.0	0.455014382462753	0.544985617537247
174.0	0.4542936996492082	0.5457063003507918
175.0	0.4535075594328481	0.5464924405671518
176.0	0.4526561947996197	0.5473438052003803
177.0	0.4517398724437276	0.5482601275562724
178.0	0.4507588927256905	0.5492411072743095
179.0	0.4497135896203785	0.5502864103796214
180.0	0.448604330655032	0.551395669344968
181.0	0.44743151683726273	0.5525684831627373
182.0	0.44619558257303465	0.5538044174269654
183.0	0.4448969955746276	0.5551030044253724
184.0	0.4435362567585818	0.5564637432414181
185.0	0.4421139001336241	0.5578860998663759
186.0	0.44063049267857496	0.5593695073214251
187.0	0.4390866342102373	0.5609133657897627
188.0	0.4374829572412672	0.5625170427587328
189.0	0.43582012682802507	0.5641798731719749
190.0	0.43409884040840896	0.565901159591591
191.0	0.43231982762966853	0.5676801723703315
192.0	0.4304838501662016	0.5695161498337984
193.0	0.42859170152733095	0.571408298472669
194.0	0.4266442068550629	0.5733557931449371
195.0	0.42464222271182783	0.5753577772881722
196.0	0.4225866368582011	0.5774133631417989
197.0	0.42047836802060645	0.5795216319793935
198.0	0.41831836564899993	0.5816816343510001
199.0	0.416107609664536	0.583892390335464
200.0	0.4138471101972138	0.5861528898027861
201.0	0.4115379073135068	0.5884620926864932
202.0	0.40918107073397175	0.5908189292660282
203.0	0.40677769954084075	0.5932223004591592
204.0	0.40432892187559333	0.5956710781244067
205.0	0.401835894626511	0.598164105373489
206.0	0.3992998031062128	0.6007001968937872
207.0	0.3967218607191721	0.603278139280828
208.0	0.39410330861921467	0.6058966913807853
209.0	0.39144541535699945	0.6085545846430005
210.0	0.3887494765174784	0.6112505234825216
211.0	0.38601681434734025	0.6139831856526597
212.0	0.3832487773724336	0.6167512226275664
213.0	0.3804467400051731	0.6195532599948269
214.0	0.3776121021419254	0.6223878978580746
215.0	0.37474628875037824	0.6252537112496217
216.0	0.37185074944688923	0.6281492505531108
217.0	0.36892695806381776	0.6310730419361823
218.0	0.3659764122068364	0.6340235877931636
219.0	0.36300063280222583	0.6369993671977742
220.0	0.3600011636341492	0.6399988363658509
221.0	0.3569795708719095	0.6430204291280905
222.0	0.35393744258718657	0.6460625574128134
223.0	0.350876388261258	0.649123611738742
224.0	0.34779803828219885	0.6522019617178012
225.0	0.34470404343206446	0.6552959565679355
226.0	0.3415960743640539	0.6584039256359461
227.0	0.3384758210696555	0.6615241789303445
228.0	0.33534499233577253	0.6646550076642275
229.0	0.332205315191832	0.667794684808168
230.0	0.3290585343468732	0.6709414656531267
231.0	0.32590641161661954	0.6740935883833805
232.0	0.32275072534052895	0.677249274659471
233.0	0.31959326978882924	0.6804067302111707
234.0	0.3164358545595317	0.6835641454404683
235.0	0.3132803039654284	0.6867196960345716
236.0	0.310128456411069	0.689871543588931
237.0	0.306982163759721	0.693017836240279
238.0	0.303843290690309	0.696156709309691
239.0	0.3007137140443385	0.6992862859556614
240.0	0.29759532216279694	0.7024046778372031
241.0	0.2944900142130409	0.7055099857869591
242.0	0.29139969950566025	0.7086003004943398
243.0	0.2883262968013273	0.7116737031986726
244.0	0.2852717336076249	0.7147282663923751
245.0	0.2822379454658572	0.7177620545341428
246.0	0.2792268752278413	0.7207731247721587
247.0	0.2762404723226808	0.7237595276773192
248.0	0.27328069201352007	0.72671930798648
249.0	0.27034949464428076	0.7296505053557192
250.0	0.2674488448763784	0.7325511551236217
251.0	0.26458071091542235	0.7354192890845777
252.0	0.2617470637278955	0.7382529362721044
253.0	0.258949876247816	0.741050123752184
254.0	0.25619112257337984	0.7438088774266202
255.0	0.2534727771535865	0.7465272228464135
256.0	0.25079681396484377	0.7492031860351562
257.0	0.24816520567755582	0.7518347943224442
258.0	0.24557992281269125	0.7544200771873087
259.0	0.24304293288833392	0.7569570671116661
260.0	0.2405561995562135	0.7594438004437865
261.0	0.2381216817282196	0.7618783182717804
262.0	0.23574133269289477	0.7642586673071052
263.0	0.233417099221912	0.766582900778088
264.0	0.23115092066652976	0.7688490793334702
265.0	0.22894472804403265	0.7710552719559673
266.0	0.22680044311414924	0.7731995568858507
267.0	0.2247199774454559	0.7752800225545441
268.0	0.22270523147175694	0.7772947685282431
269.0	0.22075809353845124	0.7792419064615488
270.0	0.21888043893887585	0.7811195610611241
271.0	0.21707412894063452	0.7829258710593655
272.0	0.21534100980190488	0.7846589901980952
273.0	0.21368291177772938	0.7863170882222706
274.0	0.2121016481162855	0.7878983518837145
275.0	0.2105990140451392	0.7894009859548607
276.0	0.20917678574747833	0.7908232142525217
277.0	0.20783671932832867	0.7921632806716713
278.0	0.2065805497707499	0.7934194502292501
279.0	0.20540998988201523	0.7945900101179848
280.0	0.20432672922976935	0.7956732707702306
281.0	0.2033324330681713	0.7966675669318287
282.0	0.20242874125401542	0.7975712587459846
283.0	0.20161726715283623	0.7983827328471638
284.0	0.20089959653499295	0.7991004034650071
285.0	0.20027728646173734	0.7997227135382626
286.0	0.19975186416126037	0.8002481358387397
287.0	0.1993248258947229	0.8006751741052771
288.0	0.1989976358122658	0.8010023641877342
289.0	0.19877172479900332	0.8012282752009967
290.0	0.19864848931099502	0.801351510689005
291.0	0.1986292902012034	0.8013707097987965
292.0	0.19871545153542802	0.801284548464572
293.0	0.1989082593982251	0.8010917406017749
294.0	0.19920896068880573	0.8007910393111943
295.0	0.19961876190691819	0.8003812380930818
296.0	0.20013882792870816	0.7998611720712918
297.0	0.2007702807725641	0.7992297192274359
298.0	0.20151419835494053	0.7984858016450594
299.0	0.20237161323616668	0.7976283867638333
300.0	0.20334351135623144	0.7966564886437686
301.0	0.20443083076055543	0.7955691692394445
302.0	0.2056344603157394	0.7943655396842606
303.0	0.2069552384152977	0.7930447615847023
304.0	0.20839395167537078	0.7916060483246292
305.0	0.20995133362042068	0.7900486663795794
306.0	0.21162806335890683	0.7883719366410932
307.0	0.21342476424894413	0.7865752357510558
308.0	0.21534200255394126	0.7846579974460588
309.0	0.21738028608822246	0.7826197139117775
310.0	0.2195400628526278	0.7804599371473722
311.0	0.22182171966009798	0.778178280339902
312.0	0.2242255807512376	0.7757744192487623
313.0	0.2267519063998627	0.7732480936001374
314.0	0.229400891508527	0.770599108491473
315.0	0.2321726641940316	0.7678273358059684
316.0	0.2350672843629148	0.7649327156370852
317.0	0.23808474227692453	0.7619152577230754
318.0	0.2412249571084706	0.7587750428915294
319.0	0.24448777548605985	0.7555122245139402
320.0	0.24787297002971173	0.7521270299702882
321.0	0.2513802378763563	0.7486197621236437
322.0	0.2550091991952118	0.7449908008047882
323.0	0.25875939569314654	0.7412406043068535
324.0	0.26263028911001823	0.7373697108899817
325.0	0.2666212597039994	0.7333787402960006
326.0	0.2707316047268797	0.7292683952731203
327.0	0.27496053688935346	0.7250394631106465
328.0	0.27930718281628486	0.7206928171837151
329.0	0.2837705814919591	0.7162294185080409
330.0	0.28834968269530975	0.7116503173046902
331.0	0.29304334542513266	0.7069566545748673
332.0	0.29785033631527624	0.7021496636847238
333.0	0.30276932803981826	0.6972306719601817
334.0	0.3077988977082196	0.6922011022917804
335.0	0.31293752525046237	0.6870624747495376
336.0	0.31818359179216715	0.6818164082078328
337.0	0.323535378019695	0.676464621980305
338.0	0.3289910625352261	0.6710089374647739
339.0	0.33454872020182486	0.6654512797981751
340.0	0.34020632047848187	0.6597936795215181
341.0	0.34596172574514145	0.6540382742548585
342.0	0.3518126896177066	0.6481873103822934
343.0	0.3577568552530288	0.6422431447469712
344.0	0.3637917536438769	0.6362082463561232
345.0	0.36991480190388887	0.6300851980961111
346.0	0.376123301542503	0.623876698457497
347.0	0.3824144367298741	0.6175855632701259
348.0	0.38878527255176637	0.6112147274482336
349.0	0.3952327532544324	0.6047672467455676
350.0	0.401753700479469	0.598246299520531
351.0	0.40834481148865903	0.591655188511341
352.0	0.4150026573787909	0.5849973426212092
353.0	0.42172368128646165	0.5782763187135384
354.0	0.4285041965828599	0.5714958034171401
355.0	0.4353403850585326	0.5646596149414673
356.0	0.4422282950981294	0.5577717049018707
357.0	0.4491638398451332	0.5508361601548668
358.0	0.45614279535656715	0.5438572046434329
359.0	0.4631607987476877	0.5368392012523123
360.0	0.4702133463266543	0.5297866536733458
361.0	0.477295791719186	0.522704208280814
362.0	0.48440334398319373	0.5155966560168063
363.0	0.49153106571339883	0.5084689342866011
364.0	0.4986738711359293	0.5013261288640707
365.0	0.5058265241929008	0.49417347580709925
366.0	0.5129836366169745	0.48701636338302545
