What are the findings of the NASA study on the Arctic permafrost?

Permafrost is soil that has remained frozen for years or centuries under topsoil. It contains carbon-rich organic material, such as leaves, that froze without decaying.
As rising Arctic air temperatures cause permafrost to thaw, the organic material decomposes and releases its carbon to the atmosphere in the form of the greenhouse gases carbon dioxide and methane. The findings of the report: 

• NASAs study has calculated that as thawing continues, by the year 2300, total carbon emissions from this region will be 10 times as much as all human-produced fossil fuel emissions in 2016.
• Southerly permafrost regions will not become a carbon source until the end of the 22nd century, even though they are thawing because other changing Arctic processes will counter the effect of thawing soil in these regions.
• The southern region may transition more slowly because plant growth may increase much faster than expected in the south. Plants remove carbon dioxide from the air during photosynthesis so increased plant growth means less carbon in the atmosphere.
• Permafrost in southern Alaska and southern Siberia is already thawing, so it is obviously more vulnerable. Some of the very cold, stable permafrost in the highest latitudes in Alaska and Siberia appeared to be sheltered from extreme climate change, and it may not be impacted over the next couple hundred years.