How to make NDVI map in Google Earth Engine || Calculated NDVI using Google Earth Engine || NDVI map

[Music] okay so hello everyone welcome can you hear me hello yes yes okay okay so basically today is our second number plus and we already covered our first day of class okay so today is our second number of class okay so let's do our today's class so just I simply share my skin then we try this sister okay okay so now can you see my skin foreign [Music] [Music] there's a number of class so only uh today I will try to discuss about that how you can easily filtering and displaying the satellite images you in Google Earth engine platform uh mainly landsat Sentinel mode is or any satellite images how can easily filtering and displaying and also export the satellite image this from the Google Earth engine platform we also try to discuss about that and then how can easily use the different types of band combination uh different types of true color composite false color composite how you can easily use the different types of band combination we also try to discuss about this then how you can easily export the satellite images from the Google attention platform and then how can easily import filter reduce clip and display data in Google Earth engine platform and how to make the time series data for ndvi again is limited time series chart then how to export any shift file from the Google Earth engine platform and how can easily calculating any indices from the satellite images such as uh ndvi NWI evi or any types of indices how can easily calculate it in Google Earth engine platform okay so let's go catalog in this art engine public data catalog we can get a lot of remote license data we can easily access and freely use so basically in this art engine public data catalog we can easily access the landsat Sentinel Modi strain land cover atmospheric data different types of satellite data surface diplier 10 stop of atmospheric raw image and all of the data set it daily updating and here you can find out that more than 200 public data set more than 400 4000 new images every single day we can get more than 5 million images more than five petabytes of data from this Earth engine public data catalog and you can see this is the acting in public data catalog link we can easily go to this link and access all of the art engine public data catalog or if you want you can simply go to your code editor and then simply click on the browse data catalog then it uh easily you can access all of the data set okay so in this time I try to discuss about that how we can use an import filter reduced clip and display data in Google Earth engine platform okay so how to import the data set uh how to filter this data then how to reduce this image collection and then how to clip on your shape file then how to display the result on the map and how to read projected this skill value Excel pixel value okay so let's go just I simply open my computer and then try to show you all of the things practically so I just simply open a new browser and simply go to my code editor okay so first of all I simply open my art engine public data catalog you can simply click on the search you can see browse data catalog simply click Twitter now I can access all of that engine all of the data from here issue just okay so now you can say I can get all of the data set landsat mode is sent in also you can see the climate uh restricted climate data atmosphere signal so that's when I have to click on here you can see the lens set here I can get all of the land City Mis collection you can see landsat 9 landsat 8 lenses seven legs at five let's hit four okay we can get all the lines collection as well as also you can center now so when I click on the Sentinel here I can get all of the center elements collection Sentinel one star data singular one two multi spectral data uh Sentinel five Sentinel three okay also you can get the some derivative data set all seen okay so also you can see Modis when I click the Modis here I can get all of the Modis uh data set uh different types of product we can easily get you can see daily product we can get some daily product different types of surface different daily transuno cover daily parallel surface temperature daily also you can see there are surface temperatures so lot of data set we can easily get for the daily we can or some derivative data set such as the leaf area index uh Terra surface Terra surface triplet you can see lens surface temperature also you can see thermal a lot of data so we can easily get in here okay in this time for the mode is when you want to work with the mode is uh all of the data set you can just follow the same process for importing for filtering for displaying the mapping for exporting all of the things will be same so in this time I just uh work with one assets suppose I want to work with the data set I want to work with this data set and try to make the ndvi map okay so this is the craft resolution indices 60 day Global 250 meter resolution so just I simply click on here I can get all of the information about this data set such as data set availability date we can get the data set between this time period it will start from 2000 um February also you can see that this is the indent okay between this time period I can access this data set and this is a data set provider also you can see the art engine snippet so basically this is the unique ID every single data set has a unique ID so in this time this unique ID this unique ID is for modestation indices 16 day Global 250 meter resolution this is data set I can find out this unique ID okay also you can see I can get all of the information about this data set also you can see how many bands are available in this data set we can find out only for the two band ndvi and evi this two band also gives a time of use so in this time I want to work with this data set so first of all I need to import the data set in my code editor so this is my correlator okay this is my code editor this coordinator I need to import this data set mainly we can import the data set in our code editor two-way if you want you can simply copy this unique ID or art engine snippet so simply copy and then paste here then paste here okay and put a variable name suppose I simply put the variable name you can put any variable name I put the variable name suppose mode is ndvi okay in this step what happened this is my full image collection of the mode is resolution this full image collection in this time I want to store it in this variable Modis and API you can put any variable name okay so now this data set is imported in my code editor this is the one way another way is that you can simply search here Modis ndvi you can simply search so now I can get all of the suggested data set for Modis and DVI I want to work with the mode is ndva this data sector obviously necessary 60 day Global 250 meter resolution I want to work with this data set I simply click on here I can get the same information all of the things will be same limitation data evaluated this information as well as this information is the same okay and when I click on here you can see now I can access this okay same place and this is the catalog view of this data set this data set catalog to when I want to click on here I can get the catalog page of this data set same data set so in this step I can simply click the import now this data set is also imported so we can import the data set in Earth engine coordinator two-way ep1 you can simply copy this Earth in the snippet and then based on your code editor and put a variable name you can use any variable name or simply search there and simply import okay so there is a two way when you want to import the data set you can follow anyone no problem okay so in this time I just simply uh follow the suppose uh you can follow the anyway okay so I simply use the first so you can see it's the default variable name image collection it's the default if you want you can change it or not it's totally different view so just I simply change it suppose I put the name mode is mdvi okay okay so now what's happened my full image collection this is the full image collection is imported in a variable this in this time this full image collection I need to filter in this time you can see this data is a two band ndvi and evi in this time I want to work with the ndvi okay so first of all I need to select this band ndvi so in this time I just simply take a variable suppose I put the variable name is that ndvi band you can use any variable name okay then I simply call the full image collection mode is mdvi in this time this variable is stored the tot all of the image collection full image collection from this full image collection I need to select only for ndvi band okay in this time I want to check how many images are available for the whole world between the time period year of 2000 from 2022 between this time period how many emails are available I want to check it for the ndvi okay so I simply use here the print function so mainly we are using the print function for printing any object any number any things then I simply call the NDP uh this variable name and paste here and use a size function so mainly size is a function is determine how many emails or image size I want to Simply click to the Run so now I can get how many emails are available between the time period from Europe 2000 to 2022 this time period here I can got total 517 images okay but in this time I also need to filter I don't need for the whole world all of the time period I don't need I need only a specific time period okay so for this when you want to filter your date we need to use the function it's called the filter date function so I simply take a variable suppose filter date 570 images this 517 images is stored in a variable this variable name is that ndvi band okay I simply call this band variable name and simply use a function filter date filtered it in this tab I simply put here the start date and indeed suppose my observation temperature is that from year of 2015 suppose first January from Europe 2020 December 31. okay so this is my observation time period so I simply select this template suppose your observation time protease is only for the one year you can simply put the year up 2015 first January from 2015 December 31 okay so in this time I work with for the total 2015 16 17 18 19 and 20. total six years data set I want to uh use for making this ndvi map okay so I simply select my time period and then now I want to check how many images are available for this time period year of 2015 to 2020 between this time period how many emails are available I want to check it but when I want to check how many emails are available between this time period just I simply use the same function I simply use at the print function and then simply call this filter date and you said the size function again so now I want to get how many images are available between this time period here I can get only 138 images okay so here I can get only 130 38 images between this time period okay so in this time if you want to check if you want to check what is the time duration uh every single images what is the time interval I want to check it just I simply user the pin function and then simply call the filter date and I click to the run so now you can check I will get every single image time interval here I can get total you can see when I simply open this 16 day you can see first image first January 2nd Ms 17 January then second February so every single Ms time interval is that 16 day that's why this data set called 16 days [Music] okay so this that is a time interval you can see the 16 day every first to the second because this uh every image time interval is the 16 day so that's why this data set called 16 day Global okay in this time I need to make the reduce the CMS collection okay so here you can see all of the image collection is not captured at the same time it's the different time period okay from the between this time period okay in this time I need to reduce this image collection okay so now I can use the different way for reducing suppose if you want you can use here the mean function even mean function is mainly calculated the average all of the 138 images it calculated the average pixel value of ndvi okay so in this time I try to show you that how can easily use the average ndpi all of the all of the total 138 images so for this I simply take a variable and put the variable name suppose ever is ever is suppose n d v i okay in this time I want to calculate it the average from this total 138 images and this 138 images is stored in a variable what is the variable name filter date I simply copy and simply paste here okay in this tag I just simply use a function reduce function reduce okay reduce is a statistical function so mainly when you want to calculate any statistical success average maximum minimum standard deviation then we can use here the reduce function and then how I can reduce I want to reduce using the average so in this term I have to reduce Earth engine reducer dot mean in this time what happened you can see I calculated total 138 images average pixel value okay and it stored the variable average ndvi I want to show the result so just I simply use at the map Dot add layer and then simply call this average ndvi and click to the Run so now you can see I can get the whole world in DVI map between this time period year of 2015 to 2022 but in this time you can see uh I did not add any leaves a color okay so that's why I can get the totally uh Ash color map look like this in this step I want to add here the visualization okay so there already provide some visualization demo code in here I just simply copy their visualization code from here simply copy and then simply paste in my code editor okay in this step what happened you can see mainly in this step they are make a dictionary you can see they make a dictionary in this dictionary they add here the min mean pixel value of ndvi it will be start from the zero and Max up to eight thousand as well as they are also using at the color gradient different types of color they are using so we already know about that in map add layer function after object name we always put visualization okay in this time my visualization variable name is that ndvi this I simply copy and then paste here okay then click to the run so now this visualization is set with this map so like you see I can get the whole world in DVI map in here okay and this time we can easily identify where the dense vegetation had the no visitation or uh moderate visitation you can easily identify from the from this map and you can see in this time uh it represented for the whole world okay ndvi map suppose in this time I don't need for the whole world I need only for the country of Bangladesh or India or any other any specific region okay I want to need this ndvi map so for this I can simply uh import my shape file okay so first class I also try to show you that part how you can easily import your own shape file from your local storage so you can easily import the shape file and you can easily clip with the shuffle then you can get the result only for the specific region okay in this time I want to work with the data set us dos data set okay and mainly USD us data set provided the international country boundary polygon and first class I also try to discuss about that how you can easily filtering this data set in this term I can get my boundary from this data set okay just like simply import and I can check it will be imported and default variable name is a travel okay if you want to change or not change it doesn't matter okay so in this time I simply filtered this table and find out my shape file boundary shape file of pantry boundary of Bangladesh or any country boundary so for this I just simply take a variable and put the variable name suppose country okay I just simply call my table this variable name because this table is storage all of the country boundary shape file okay in this tab I want to filter this tab on so I simply user the filter then I Define how I can filter it I want to filter Earth engine filter equal what's equal what I simply put here the country name such as suppose banglades I simply put this Bangladesh in this type what happened you can see this Bangladesh country boundary shape file is stored at the variable country okay in this time I want to Simply use here a clip function I simply user the clip function and clip with boundary and my boundary is the Bangladesh and this Bangladesh boundary shape file is stored in a variable country I simply copy and paste here okay then click to the run in this term I can get the result only for the 340 of Bangladesh you can see it will be loaded okay but you can see it look very small in this type I want to add here the map Center object function so that's why it will be automatically focus on the center so let's go just I simply use a function map Dot Center object either simply in this demo object is the shape file suppose this special country I simply paste here and then user doesn't and click to the run so now we can see it automatically forecasts of this country boundary shape file I can get the result [Music] so I can see I can get the whole country boundary uh ndva map of Bangladesh between this time period okay so now you can easily export this map and you can easily work with the arcmap software for making your making your presentation map or research paper map okay I also try to show you the letter in this time suppose I want to read the map for the another country just I simply put here the suppose uh and of any country suppose say the RV I simply put and click to the run so now I can get the result for the Saudi Arabia ndva map between this time period so now you can see I can easily get this uh so there will be a continental shape file and this ndvm app in here so here you can see very less vegetation we can find out in here okay so any country so we can simply put this name suppose I simply put this country boundary success any country boundary in the world suppose I simply put this name suppose Pakistan foreign you can easily change the time period according to your uh observation time period you can simply change this time period and you can easily get the result okay so you can say now I can get the ndvmf for the Pakistan okay in this time in this map has a problem this problem is that we can easily find out the problem when I want to click on the inspector tab you can see in a spectator when click on this any portion of the map you can say I can get the result look like this 4182 when I click I can get the result you can see uh 1251 but ndvi value mainly uh if this range is that negative one to positive one but

Channel: Study Hacks-Institute of GIS & Remote Sensing

Views: 6,400

Keywords: #NDVI, remote sensing, remote sensing and gis, remote sensing lecture, remote sensing geography, GIS, google earth engine, google earth engine tutorial for beginners, google earth engine tutorial, google earth engine python, vegetation index, normalized difference vegetation index, enhanced vegetation index

Id: LXrTYcUYXgc

Length: 24min 22sec (1462 seconds)

Published: Mon Jan 16 2023