Near-future climate change (decades to century scale) must be viewed in the context of past climate change. Baselines, rates of change and natural variability are all important aspects of climate change and must be taken into account when making land/resource use and natural hazards decisions.
Marine sediments record past paleoclimate and paleoceanographic changes. We have focused on the Gulf of Mexico because these sediments preserve a record of North American climate change. Periods of intense freshwater runoff following the last ice age are preserved in Gulf of Mexico sediments. Likewise, extended episodes of flooding and drought are recorded in river flow data during the last century and similar events throughout the Holocene should be recorded in high accumulation rate sequences in the Gulf of Mexico. An annual summer monsoon is responsible for wet conditions in parts of the south from New Mexico to Florida. Variability in monsoon strength should be recorded in the planktic foraminiferal assemblages from the western Gulf of Mexico.
Many techniques exist to extract paleoclimate information from marine sediments. All faunal based reconstructions rely on a temporally
well-constrained calibration data set representing modern or "near" modern conditions. We present faunal census data generated from analysis of surface sediment samples taken in the northwestern Gulf of Mexico on cruise 94H of the Texas A&M University research vessel R/V Gyre. This work is one component of the USGS effort to develop a robust and well-dated planktic foraminifer calibration data set.
