Sunday, October 2, 2011

Water Fight on the River - Round Twelve

12. Question. Did the Lands of Nephi and Zarahemla share a similar climate? See the article "Asking the Right Questions" in this blog.

12. Answer. No.
12. Exhibit. To test the two rivers, we will compare meteorological data from Guatemala City (Nephi) with data from Tuxtla Gutierrez in the Mezcalapa-Grijalva basin, and from the city of Balancan in the Usumacinta basin. Our sources are Instituto Nacional de Estadistica y Geografia (INEGI) and Servicio Meteorologico Nacional (SMN) (a division of CONAGUA) in Mexico, and Ministerio de Agricultura, Ganaderia y Alimentacion (MAGA) in Guatemala. The chart shows four key climate measurements for the three locations: mean annual temperature in degrees Celsius, mean annual relative humidity expressed as a percent, mean annual precipitation in millimeters, and mean annual days with measurable precipitation, aka rainy days. In other words, we are measuring how hot, humid, and wet the climates are in these three places. Click on the chart to expand it to full-size (the same holds true for all images on this blog).
Key Climate Variables for Guatemala City, Guatemala;
Tuxtla Gutierrez, Chiapas on the Mezcalapa-Grijalva;
and Balancan, Tabasco on the Usumacinta.
The Koppen climate classification system has been the de facto world standard for well over a century. We compare our areas of interest on Koppen climate maps of Mexico and Guatemala. The Mexican map is from the University of Texas which maintains one of the largest collections of Mesoamerican maps (Perry-Castaneda Collection) in the world. The Guatemalan map is from MAGA.
Koppen Climate Map of Mexico.
Koppen Climate Map of Guatemala.
The maps show that Guatemala City and Tuxtla Gutierrez both have an Aw climate classification. This is a sub-tropical savanna climate with distinct wet and dry seasons, often found on the margins of tropical areas. Balancan, on the other hand, has an Af tropical rain forest climate classification with precipitation more or less year-round.
12. Conclusion. Even though Tuxtla Gutierrez is considerably lower in elevation (540 meters) than Guatemala City (1,560 meters), and therefore hotter, the two places have the same sub-tropical climate (Koppen Aw) with very similar amounts of annual precipitation and average relative humidity. Balancan, Tabasco, on the middle Usumacinta, though, is a completely different story. Balancan is tropical - hotter, more humid, with more than twice as much rainfall and many more rainy days. It is understandable why Zeniff was "over-zealous" Mosiah 7:21 to escape the stifling mugginess of the middle Usumacinta and return (at great risk to himself and his followers) to the balmy highlands of Guatemala. (Guatemala City is justifiably famous for its invigorating climate that the locals call "eternal spring.") The Mezcalapa-Grijalva does not fit this criterion. The Usumacinta fits it very well. Advantage Usumacinta. 
12. Running Score. Mezcalapa-Grijalva 0. Usumacinta 12.