Correction: Yadav. K. and Congalton. R. Accuracy Assessment of Global Food Security-Support Analysis Data (GFSAD) Cropland Extent Maps Produced at Three Different Spatial Resolutions. Remote Sens. 2018, 10, 1800

This research paper [1] presented the accuracy assessment of the published cropland extent maps created by the GFSAD team and which are available for download from LPDAAC. It is very important to provide all the references for these maps. Therefore, after publication of this research paper [1], the authors wish to make the following additions to this paper. These additions are citations that were inadvertently left out of the original paper. Citations are added to the text and to figures and tables, where appropriate.

In the abstract, the original sentence ‘An accuracy assessment and comparison of these three GFSAD cropland extent maps was performed to establish their quality and reliability for monitoring croplands both at global and regional scales’ should be updated as ‘An accuracy assessment and comparison of these three GFSAD cropland extent maps produced and published by different researchers was performed to establish their quality and reliability for monitoring croplands both at global and regional scales’.

In the introduction section, the references from [5–7] should be updated to include [5–18]. In the Datasets section,

Table 2. Description of the three different GFSAD cropland extent maps.

Datasets	Year	Spatial Resolution	Input Data	Assessment Regions	Classification Scheme	Source	References
GFSAD1km	2010	1 km	Existing cropland extent maps	Entire world (8 Regions)	Irrigated and Rain-fed cropland classes	https://lpdaac.usgs.gov/dataset_discovery/measures/measures_products_table/gfsad1kcm_v001	[5]
GFSAD250m	2008,2014	250 m	MODIS	4 Continents (US, Africa, Australia, and South-Asia)	Cropland and Non-Cropland	Africa: https://lpdaac.usgs.gov/node/1276 North-America: https://lpdaac.usgs.gov/node/1277 South-America: https://lpdaac.usgs.gov/node/1278 Europe, Central Asia, Russia, Middle-East: https://lpdaac.usgs.gov/node/1279	[6–8]
GFSAD30m	2014	30 m	Landsat	Entire world (15 regions)	Cropland and Non-Cropland	South-Asia: https://lpdaac.usgs.gov/node/1280 South-East Asia: https://lpdaac.usgs.gov/node/1281 Australia, China, New Zealand, Mongolia: https://lpdaac.usgs.gov/node/1282	[9–18]

should be updated with an additional reference column presenting [5], [6–8], and [9–18] in each row (as shown below). In the Conclusions section, “The assessment report of the GFSAD30m cropland extent map is available online at https://lpdaac.usgs.gov [64]” must be updated at the end of the first paragraph.

The caption of Figure 2 should be updated with ‘The GFSAD 1 km [5], 250 m [6–8], and 30 m [9–18] cropland extent maps generated by multiple producers.

The caption of Figure 5 should be updated with ‘The distribution of the eight regions along with the entire reference data set of 1800 samples (Source: Geo-Wiki) used in the assessment of GFSAD1km cropland extent map’.

The caption of Table 6 should be updated with ‘Regions, their area, and number of samples (Source: GeoWiki) that were used to assess the GFSAD1km Cropland extent map’.

The caption of Figure 6 should be updated with ‘The distribution of reference samples distributed in the four regions (Source: Independent datasets generated by assessment team and field data collected for Australia [6,11]) used to assess GFSAD250m cropland extent map’.

The caption of Figure 7 should be updated with ‘The distribution of regions and reference samples (Source: Independent reference datasets generated by assessment team from CDL and high-resolution imagery and field data collected for Australia [6,11]) used to assess the GFSAD30m cropland extent map’.

In the Discussion section, the first sentence ‘With the release of three different resolution GFSAD cropland extent maps, it becomes crucial to know their individual accuracy and similarity to make a choice on using these maps in different agriculture field sizes’ should be updated with the citation [5–18].

In the Conclusions section, the second sentence should be updated as ‘With the recent release of the three different GFSAD cropland extent maps produced by different researchers, their quality and reliability must be evaluated at global and regional scales’.

The references section should be updated as follows to include those that we inadvertently left out:

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The above changes do not impact the scientific results. The manuscript will be updated, and the original will remain online on the article webpage, with a reference to this correction. We apologize for any inconvenience caused by this mistake. Including these additional references will make it easier for the reader to understand the crop maps the analysis in this paper used.