/**** Start of imports. If edited, may not auto-convert in the playground. ****/
var top = ee.FeatureCollection("projects/sat-io/open-datasets/open-ocean/aqualink_top_temp_2020"),
    bottom = ee.FeatureCollection("projects/sat-io/open-datasets/open-ocean/aqualink_bottom_temp_2020");
/***** End of imports. If edited, may not auto-convert in the playground. *****/
print('Top readings',top.size())
print('Bottom readings',bottom.size()) 

Map.centerObject(top.first(),7)
Map.addLayer(top)

// Define the chart and print it to the console.
var chart =
    ui.Chart.feature
        .histogram({features: top, property: 'value', maxBuckets: 50})
        .setOptions({
          title: 'Top temp',
          hAxis: {
            title: 'Top temp (C)',
            titleTextStyle: {italic: false, bold: true}
          },
          vAxis: {
            title: 'Observation count',
            titleTextStyle: {italic: false, bold: true}
          },
          colors: ['1d6b99'],
          legend: {position: 'none'}
        });
print(chart);

// Define the chart and print it to the console.
var chart =
    ui.Chart.feature
        .histogram({features: bottom, property: 'value', maxBuckets: 50})
        .setOptions({
          title: 'Bottom temp',
          hAxis: {
            title: 'Bottom temp (C)',
            titleTextStyle: {italic: false, bold: true}
          },
          vAxis: {
            title: 'Observation count',
            titleTextStyle: {italic: false, bold: true}
          },
          colors: ['1d6b99'],
          legend: {position: 'none'}
        });
print(chart);