Saturday, September 24, 2011

Water Fight on the River - Round Six

6. Question. What was the nature of the Land of Zarahemla - Land of Nephi relationship during the Nephite/Lamanite wars? See the article "Asking the Right Questions" in this blog.

6. Answer. Repeated Lamanite attacks with little or no warning on less densely-populated Nephite lands.
6. Exhibit A. We established previously that the Mezcalapa-Grijalva area was relatively more densely- populated in antiquity than the Usumacinta region. See the article "Water Fight on the River - Round Three" in this blog. We will now compare both river basins with the highland Guatemala territory where scholarly consensus places The Book of Mormon's land of Nephi. We begin by drawing three polygons colored blue for the Mezcalapa-Grijalva basin, red for the Usumacinta basin, and yellow for the contiguous land of Nephi (meaning that portion of the land of Nephi not already contained within one or the other river basin). We then overlay this colored map with EAAMS data showing known archaeological sites.
Mezcalapa-Grijalva basin in blue,
Usumacinta basin in red,
Contiguous land of Nephi in yellow.
Google Earth can calculate the area of each of the three polygons. Results: Mezcalapa-Grijalva basin 46,772 square kilometers, Usumacinta basin 97,150 square kilometers, contiguous land of Nephi 22,657 square kilometers. We then count the number of known archaeological sites within each polygon. Results: Mezcalapa-Grijalva 708, Usumacinta 577, contiguous land of Nephi 264. Dividing the number of sites by the number of square kilometers gives us the number of known archaeological sites per square kilometer in that area. Results: Mezcalapa-Grijalva .015, Usumacinta .006, contiguous land of Nephi .012.
Density of known archaeological sites per square kilometer.
6. Conclusion A. The Usumacinta River basin fits the expected pattern for this criterion. It was less densely-occupied in antiquity than highland Guatemala. The Mezcalapa-Grijalva River basin contravenes our expected results. It was more densely settled in antiquity than the highlands south of it. Advantage Usumacinta.
6. Exhibit B. Environmental conditions that would allow a Lamanite army to approach Nephite-held territory practically undetected might include:
  • Nearby jungle - dense vegetation, tall trees 
  • Storminess - precipitation, heavy cloud cover
  • High relative humidity that reduces visibility.
We established previously with NASA data that the Mezcalapa-Grijalva basin is largely unforested while the Usumacinta basin has huge areas covered with tall trees. See the article "Water Fight on the River - Round Five" in this blog. The Mexican Instituto Nacional de Estadistica y Geografia (INEGI) publishes excellent data showing areas of dense vegetation which we overlay on top of our base map of the two river basins. Unfortunately, INEGI data stops at the Guatemala border. If it did not, you would see much more bright green in the Usumacinta region.
Mexican areas covered with dense vegetation.
Fortunately, NASA Terra/MODIS data ignores national boundaries. This is their land cover classification index that shows large sections of the Usumacinta basin covered with evergreen broadleaf forest.
Land Cover Classification.
This INEGI rainfall map of Mexico clearly shows that the middle and upper Mezcalapa-Grijalva area is drier than the Usumacinta region.
Rainfall map of Mexico.
And this map from the Guatemalan Instituto Nacional de Sismologia, Vulcanologia, Meterologia e Hidrologia (INSIVUMEH) shows large areas along the Usumacinta that get more than 175 days of rain each year.
Guatemalan map of rain days per year.
With that many annual rain days, you can imagine what the relative humidity is like. This map, also from INSIVUMEH, shows that the annual average relative humidity in the Usumacinta River area is over 85%. By contrast, the annual average number for both Tuxtla Gutierrez, Chiapas, and Guatemala City is a more moderate 75%.
Average annual relative humidity in Guatemala.
6. Conclusion B. In each of the 3 criteria we have considered that may have allowed a Lamanite army to sneak up on the Nephites largely undetected - 1) dense vegetation, 2) storminess, and 3) relative humidity, the Usumacinta fits The Book of Mormon text better than the Mezcalapa-Grijalva. Advantage Usumacinta.
6. Running Score. Mezcalapa-Grijalva 0. Usumacinta 6.