Google Earth Engine（GEE）—— GEDI L2A Raster数据中轨道数量orbit_number暂时无法获取
GEDI L2A Raster Canopy Top Height (Version 2)
全球生态系统动态调查（GEDI）任务旨在确定生态系统结构和动态的特征，以便从根本上改善对地球碳循环和生物多样性的量化和理解。附属于国际空间站（ISS）的GEDI仪器在全球范围内收集北纬51.6°和南纬51.6°之间的数据，对地球的三维结构进行最高分辨率和最密集的采样。
GEDI的2A级地理位置海拔和高度指标产品（GEDI02_A）主要由100个相对高度（RH）指标组成，它们共同描述了GEDI收集的波形。
原始的GEDI02_A产品是一个点的表格，空间分辨率（平均足迹）为25米。数据集LARSE/GEDI/GEDI02_A_002_MONTHLY是原始GEDI02_A产品的栅格版本。光栅图像被组织为相应月份的单个轨道的月度合成。只有根级RH值和它们相关的质量标志和元数据被保留为栅格带。每个GEDI02_A_002栅格有136个波段。
GEDI L2A矢量数据可以在表集LARSE/GEDI/GEDI02_A_002中找到。
GEDI L4B生物量数据可以在图像LARSE/GEDI/GEDI04_B_002中找到。
更多信息见用户指南。
数据介绍中的轨道数量，并未再数据出现，所以现在这个波段无法使用
代码：
var gedi = ee.ImageCollection("LARSE/GEDI/GEDI02_A_002_MONTHLY"),
garda =
/* color: #98ff00 */
/* shown: false */
ee.Geometry.Polygon(
[[[10.668700253969874, 45.721177921166806],
[10.522444760805811, 45.61465374845639],
[10.506651914126124, 45.602164682813914],
[10.537550961977686, 45.57765882323229],
[10.536864316469874, 45.54160135752743],
[10.501158750063624, 45.506964420644486],
[10.508711850649561, 45.47952838786983],
[10.576003110415186, 45.45400569877153],
[10.62678299743152, 45.445515211997346],
[10.68184439653804, 45.43603586355283],
[10.71205679888179, 45.45482381812902],
[10.745702428764602, 45.51596174143399],
[10.705876989311477, 45.605083724965134],
[10.812993688530227, 45.73463562440732],
[10.883718175834915, 45.829928230754355],
[10.88509146685054, 45.8734499783324],
[10.855565710014602, 45.89256964186901],
[10.829473180717727, 45.884444588859814]]]),
como =
/* color: #0b4a8b */
/* shown: false */
ee.Geometry.Polygon(
[[[9.294323856598314, 46.15232807791275],
[9.255185062653002, 46.139007729128444],
[9.271664554840502, 46.08426534873739],
[9.234585697418627, 46.03995565738929],
[9.200940067535814, 45.98129789646509],
[9.124722416168627, 45.94884251230448],
[9.117855961090502, 45.929264636130156],
[9.132275516754564, 45.88865433475716],
[9.085583622223314, 45.86140490130992],
[9.060864383942064, 45.82313754531954],
[9.076657230621752, 45.807344592793264],
[9.095883304840502, 45.820744961619525],
[9.120602543121752, 45.84610111744691],
[9.16386121011394, 45.86283941513467],
[9.159054691559252, 45.92783183719575],
[9.205746586090502, 45.94120318795341],
[9.255185062653002, 45.97795777897051],
[9.260678226715502, 45.96698168853763],
[9.296383793121752, 45.90824654243971],
[9.332776005035814, 45.87909465167566],
[9.360241825348314, 45.8561447006154],
[9.382901127106127, 45.82840086753721],
[9.41105359292644, 45.8001644973964],
[9.426159794098314, 45.813088002833084],
[9.406933719879564, 45.83462051584403],
[9.38633435464519, 45.86618647011851],
[9.368481571442064, 45.88530863279725],
[9.338955814606127, 45.902512953314556],
[9.315079773655155, 45.9455267912581],
[9.30272015451453, 45.98036993499429],
[9.292420471897342, 46.02043630067316],
[9.315079773655155, 46.045224749368636],
[9.321259583225467, 46.09524445722314],
[9.359025086155155, 46.12333087786766],
[9.394044007053592, 46.15615955335599],
[9.37413128732703, 46.180411646506464]]]),
magi =
/* color: #ffc82d */
/* shown: false */
ee.Geometry.Polygon(
[[[8.796373808845907, 46.17390356998231],
[8.791223967537313, 46.15725915820612],
[8.779894316658407, 46.15274052031653],
[8.764788115486532, 46.1567835295847],
[8.746248686775594, 46.15963723964677],
[8.704019988045125, 46.12871416417427],
[8.684415682375736, 46.09712958809706],
[8.703456072881162, 46.02940791620408],
[8.671183734013974, 46.02297168018343],
[8.578242002568505, 45.94404148882621],
[8.558672605595849, 45.919924200807294],
[8.541334806523583, 45.93258111509623],
[8.498247800908349, 45.9459513208292],
[8.475648509737436, 45.92864815061122],
[8.503610689837489, 45.894940589076455],
[8.55443635815877, 45.8777051407197],
[8.57040086621541, 45.8404057260641],
[8.556153456412193, 45.82760919046737],
[8.534867445670006, 45.80308230306516],
[8.5400172869786, 45.77540537576399],
[8.583120737663581, 45.721652331343925],
[8.623289499870612, 45.720334026369294],
[8.627750322689382, 45.730650109334526],
[8.57487861858782, 45.77760183319491],
[8.593418047298757, 45.793881977250614],
[8.634956264406748, 45.82789309853573],
[8.604743862062998, 45.898660963124456],
[8.759925746828623, 46.016089336834405],
[8.740699672609873, 46.08852232795945],
[8.851936244875498, 46.13231720100465],
[8.873908901125498, 46.16276267619395],
[8.832710170656748, 46.18463496044165]]]),
iseo =
/* color: #00ffff */
/* shown: false */
ee.Geometry.Polygon(
[[[10.076915319169201, 45.82067286483499],
[10.065808668127412, 45.80806201068483],
[10.07010020255124, 45.80435245805046],
[10.05585230826413, 45.80267709524415],
[10.045724287023896, 45.7786181177919],
[10.034222974768037, 45.77251194927582],
[10.033252099339064, 45.75984379417108],
[10.04235015231758, 45.746308985493705],
[10.04932231169342, 45.733342250827995],
[10.042112533861388, 45.71692457849758],
[10.052179673727961, 45.69204712341181],
[10.035185197409602, 45.68629124414831],
[9.953472976175961, 45.67191814066297],
[9.953816298929867, 45.665440404822775],
[9.962399367777524, 45.65932185485305],
[9.968922500101742, 45.658841940301556],
[9.993690647862298, 45.66403771414404],
[10.005020298741204, 45.658278953104016],
[10.019688636882046, 45.65679293587198],
[10.027112991435269, 45.65919255530434],
[10.030846626384, 45.658772629327025],
[10.055392087393317, 45.651164041929945],
[10.087664426260504, 45.667960906879124],
[10.118563474112067, 45.70537579281401],
[10.079424680166754, 45.77917273104895],
[10.11925011961988, 45.80071835547786],
[10.086977780752692, 45.82656211116038]]]),
idro =
/* color: #0b4a8b */
/* shown: false */
ee.Geometry.Polygon(
[[[10.462653484563615, 45.73830670876514],
[10.461151441387058, 45.73562591237109],
[10.462996808734145, 45.73540125878868],
[10.46527133126686, 45.73782746970118],
[10.467932093493932, 45.73615010057241],
[10.469519967722194, 45.736120147097054],
[10.469949122918301, 45.736314844418565],
[10.473169756716272, 45.73961198618817],
[10.479349591554199, 45.73913275832917],
[10.486559398854547, 45.74715928256184],
[10.521406800963275, 45.766322433282134],
[10.525355028857227, 45.78128906587667],
[10.520376828562824, 45.78679577567215],
[10.536684726240304, 45.80020114241897],
[10.536341402112113, 45.805586319246046],
[10.525355028983743, 45.80977443026576],
[10.521750125305417, 45.81300504360083],
[10.511965386708125, 45.81186836770156]]]);
print("gedi",gedi)
var range = gedi.reduceColumns(ee.Reducer.minMax(), ["system:time_start"]);
print('Date range: ', ee.Date(range.get('min')), ee.Date(range.get('max')));
// old band name, including orbit and other information
print(gedi.first().select('shot_number'));
// error: no band named orbit_number
print(gedi.first().select('orbit_number'));
var first_image = gedi.first();
var firstdate = ee.Date(first_image.get('system:time_start'));
print(firstdate);
print('bands first image',first_image.bandNames());
var gedi_filtered = gedi.filterDate( ee.Date(range.get('max')).advance(-1,'day'), ee.Date(range.get('max')).advance(1,'day'));
var last_image = gedi_filtered.first();
print(ee.Date(last_image.get('system:time_start')));
print(last_image.bandNames());
//print(img1.get('system:time_start'))
//print(img2.get('system:time_start'))
var gedi_filtered_como = gedi.filterBounds(como);
var como_first = gedi_filtered_como.first();
var firstdate_como = ee.Date(como_first.get('system:time_start'));
print('firstdate_como', firstdate_como)
print('bands first image como',como_first.bandNames());
Map.addLayer(gedi_filtered_como);
Map.centerObject(gedi_filtered_como);
var gedi_filtered_b = gedi_filtered_como.filterDate( ee.Date(range.get('max')).advance(-1,'day'), ee.Date(range.get('max')).advance(1,'day'));
var last_image_como = gedi_filtered_b.first();
print('last_image_como', ee.Date(last_image_como.get('system:time_start')));
print('last_image_como bands',last_image_como.bandNames());
var gedi_filtered_como_mosaic = gedi_filtered_como.mosaic()
print('gedi_filtered_como_mosaic',gedi_filtered_como_mosaic.bandNames());
