Short-term and long-term drought status maps for New Mexico, prepared by the state's drought monitoring group, are available here

The meteorological drought status ("state of the land" drought assessment) for July 14 indicated that much of north central New Mexico was in a severe drought emergency with the southern part of the state in a drought warning status.

The hydrologic drought status ("state of the hydrology") for July 14 indicated moderate to severe drought conditions in many basins.

The El Malpais tree-ring record is most closely associated with precipitation over a 13-month period covering July through the following July. The top graph in the image below right shows the close association between the tree-ring reconstruction and observed 13-month July-July precipitation for the Southwestern Mountains of New Mexico (Climate Division 4) for the last 100 years. The comparison shows that the droughts of the 1950s and early 1900s are well represented by the tree-ring reconstruction of precipitation.

The bottom graph to the right shows the 10-year moving mean of the precipitation reconstruction for the last two millennia. While the 20th century dry events were quite severe, the reconstruction shows that several earlier droughts were more severe and lasted much longer. A number of the severe droughts of the past spanned several decades, the most recent occurring in the second half of the 16th century. Other notable examples are the dry spells in the middle of the 15th century, in the 12th and 13th centuries, in the middle of the sixth century, and the prolonged period of dryness which stretched across most of the fourth and fifth centuries. Overall, this reconstruction suggests that severe, long-duration (longer than 10 years) droughts are a common feature of New Mexico's climate.

Dr. Thomas Swetnam and colleagues from the University of Arizona have collected samples from fire scarred trees for a large number of sites in New Mexico and Arizona. From these collections, Dr. Swetnam and Merrick Richmond have developed a set of maps that compares large fires for 2002 and 2003 with fires in the tree-ring record for 1748 - see the maps here.

Their analysis of tree-ring data from 55 forest and woodland sites in Arizona, New Mexico and northern Mexico provides a wildfire chronology for the last 400 years. As noted by Dr. Swetnam and his colleagues, investigating the fire regimes of the United States during pre- and post-Euro-American settlement periods can give important clues to current and future fire activity for the region. It can also help explain current fire behavior, and help inform future management decisions. Fire regimes can be described by creating fire histories: the actual record of fires for a particular geographic area. A variety of techniques can be used to compile fire histories, including building chronologies from fire scarred trees, forest age and stand structure reconstructions using dendrochronology, repeat photographs, historical writings, and early land survey records.

As seen in the bottom time series, large, regional fire years were common during the pre-settlement era. Typically, years with wildfires across much of the region are dry years that follow a sequence of one to three wet years. The year 1748 stands out with nearly two-thirds of the sites showing evidence of wildfire, followed by 1851 and 1861 as particularly volatile years. The long periods of time without fire during the 20th century are anomalous for many of the sampled forest types in the region. However, fire severity has increased in many forest types in recent decades, at least in part due to the high forest fuel load resulting from fire suppression starting at the turn of the last century.

Grissino-Mayer, Henri D. 1995. The climate and fire history of El Malpais National Monument, New Mexico. Ph.D. dissertation, The University of Arizona, Tucson. 407 pp.

Grissino-Mayer, Henri D. 1996. A 2129 year annual reconstruction of precipitation for northwestern New Mexico, USA. In Dean, J.S., Meko, D.M., and Swetnam, T.W., eds., Tree Rings, Environment, and Humanity. Radiocarbon 1996, Department of Geosciences, The University of Arizona, Tucson: 191-204.

Grissino-Mayer, Henri D., Swetnam, Thomas W., and Adams, Rex K., in press. The rare, old-aged conifers of the malpais. In Zidek, J., ed., The Natural History of El Malpais. Santa Fe, NM: National Park Service, Southwestern Region.

Swetnam, T. W., C. D. Allen, and J. L. Betancourt. 1999. Applied historical ecology: Using the past to manage for the future. Ecological Applications 9(4): 1189-1206.

The WDC Paleoclimatology archive contains the El Malpais Precipitation Reconstruction Data and Data Description.