Rosario Romero-Centeno

Isthmus of Tehuantepec Wind Climatology and ENSO Signal

Abstract The statistical characteristics of the winds at the Isthmus of Tehuantepec and their seasonal and interannual variability are studied through the analysis of several datasets and a reconstruction of the winds for a 31-yr period. Observations show that the long-term monthly mean wind speeds and frequency of occurrence of northerly winds have a strong seasonal signal, with maximum values during December–January, minimum during May–June, and a relative maximum in July. The frequency distribution of wind speed is bimodal, a feature that is closely related to the wind direction, with northerly winds being stronger. Based on these results and the close relationship between the across-Isthmus pressure differences and the local winds, a statistical model is developed to get a reconstruction of 12-hourly winds through the Isthmus of Tehuantepec for 1964–95. The model reproduces fairly well the main characteristics of the observed winds: the bimodal distribution of the wind speed and the seasonal signal in...

Midsummer Gap Winds and Low-Level Circulation over the Eastern Tropical Pacific

Abstract The low-level seasonal and intraseasonal wind variability over the northeastern tropical Pacific (NETP), its relationship with other variables, and the connection with large- and middle-scale atmospheric patterns are analyzed using a suite of datasets. Quick Scatterometer (QuikSCAT) wind data show that the low-level circulation over the NETP is mainly affected by the northerly trades, the southerly trades, and the wind jets crossing through the Tehuantepec, Papagayo, and Panama mountain gaps. The seasonal and intraseasonal evolution of these wind systems determines the circulation patterns over the NETP, showing predominant easterly winds in winter and early spring and wind direction reversals in summer over the central region of the NETP. During summer, when southerly trades are the strongest and reach their maximum northward penetration, weak westerlies are observed in June, easterlies in July–August, despite that strong southerlies tend to turn eastward, and again westerlies in September–Octob...

Landfalling tropical cyclones on the Pacific coast of Mexico: 1850-2010

Historical documents and newspapers from Mexican Pacific states (north of 14o N) were reviewed to determine the incidence of landfalling tropical cyclones from 1850 to 1949, prior to the start of the United States National Hurricane Center database. The reviewed documents are only found in Mexican repositories at national, state and municipal level and the systematic search embarked upon in this study yielded valuable information that cannot be found elsewhere. A time series of landfall was reconstructed back to 1850, indicating active and quiet periods. An average of 1.8 ± 1.6 landfalls per year is determined from the time series for 1850-2010. When the series is limited to 1880-2010, eliminating the first 30 years that may have some undercounting, the average increases to 2.1 ± 1.6 cases per year. Spectral and wavelet analysis of the 161 years of landfalling tropical cyclones indicates that the Pacific Decadal Oscillation (PDO) modulates the activity. The influence of El Nino/Southern Oscillation(ENSO) and the North Atlantic Oscillation (NAO) on the landfall frequency may be present throughout the reconstruction period but both oscillations have lower correlations compared to that from the PDO.

Observations and Forecasts from the Landfall of Tropical Cyclones John, Lane, and Paul (2006) over Northwestern Mexico

AbstractThis study focuses on track and intensity changes of three tropical cyclones that, during the season of 2006, developed in the eastern North Pacific basin and made landfall over northwestern Mexico. Observational datasets, including satellite and radar imagery and a rain gauge network, are used to document regional-scale structures. Additionally, gridded fields are applied to determine the large-scale environment. John made landfall as a category-2 hurricane on the Saffir–Simpson scale and moved along the Baja California Peninsula during more than 40 h, resulting in total rainfall of up to 506 mm. The largest accumulations were located over mountains and set new records with respect to daily rates from the 1969–2005 period. Later in the season, Lane and Paul made landfall over the mainland and brought moderate rainfall over the coastal plains. Lane became a category-3 hurricane and was the third strongest hurricane to make landfall since 1969. In contrast, Paul followed a recurving track to reach ...

Analysis of Ocean Current Observations in the Northern Veracruz Coral Reef System, Mexico: 2007–12

ABSTRACT Allende-Arandía, M.E.; Zavala-Hidalgo, J.; Romero-Centeno, R.; Mateos-Jasso, A.; Vargas-Hernández, J.M., and Zamudio, L., 2016. Analysis of ocean current observations in the northern Veracruz Coral Reef System, Mexico: 2007–12. The Veracruz Coral Reef System (VCRS) is a marine protected area located on the continental shelf of Veracruz, in the SW Gulf of Mexico, that is formed by two reef conglomerates: one to the north, in front of the Port of Veracruz, and one to the south, in front of the Antón Lizardo tip. To characterize the currents and their variability for the northern reefs of the VCRS, ocean currents, meteorological parameters, and sea-level observations for the period 2007–12 were analyzed. The temporal variability of the currents was dominated by 2- to 10-day lasting events associated with the atmospheric synoptic conditions through the forcing of the along-coast wind-stress component over the Tamaulipas-Veracruz shelf. During autumn–winter, strong episodic southeastward currents prevailed, reaching more than 1 ms−1, and they were associated with the intrusion of atmospheric high-pressure systems into the Gulf of Mexico. However, some episodes of strong southeastward currents observed in spring–summer were forced by low-pressure systems (tropical storms). From May to August, weak northwestward currents were predominant, with speeds lower than 0.40 ms−1. Annually, southeastward (northwestward) currents were observed 45–60% (40–55%) of the time, with an average of 55% (45%). Tidal currents are one order of magnitude weaker than the wind-driven currents. A multiple linear regression model for the along-shelf currents, which is based on the wind stress, explains most of the observed variance and performs well in reproducing the autumn–winter strong southeastward events but underestimates those observed in summer.

Digital Atlas of Mexico Provides Accessible Climate Information

Modern geomatic technologies—and particularly geoscientific, digital, and online multimedia cartography—represent one response to the growing demand for climatic information by the scientific community and general users. The Digital Climatic Atlas of Mexico (DCAM) fills the need to have readily accessible climate information about Mexico, Central America, and adjacent areas in preconfigured or user-configured georeferenced maps. The atlas provides information about the continental and oceanic climate, bioclimatic variables, and socioeconomic indicators (Figure 1).