Juan Estrella Martinez

 

Background:

Juan Estrella Martínez is originally from the town of Camuy. He obtained a bachelor's degree in science in Physical Sciences from the University of Puerto Rico in Mayagüez. He is currently a student of Dr. Amos Winter and studies Caribbean climate change through the use of carbonate proxies. He is an animal lover (owns two dogs and two cats with his parents and has owned many other types of pets) and loves going for rides in his mountain bike.

 

Research:

Abstract to be presented in the American Geophysicist Union (AGU) Meeting of the Americas 2013 in Mexico. A similar abstract was presented in the AGU Fall Meeting in San Francisco in 2011 and encompasses the core of my research:

 

We present a high-resolution (annual) record of the Caribbean mixed layer temperature at different depths derived from oxygen isotopic ratios obtained from the sclerosponge Ceratoporella nicholsoni. Sclerosponges precipitate their calcium carbonate skeleton in equilibrium with their surrounding environment and are capable of living at depths down to 200 m. The sponges for this project were collected off the coasts of Puerto Rico and the US Virgin Islands in northeastern Caribbean Sea. The records obtained extend from the early 1500’s to the present and suggest that the northeastern Caribbean was 1 – 2 °C cooler than present during the Little Ice Age.  Wavelet time-series analysis of our sclerosponge records indicates that when the total solar irradiance (TSI) reaches a threshold value of 1365.29 Wm^-2 there is a coupling of the eleven-year sunspot cycle with SST variability such that  TSI was able to explain more than 35% of the decadal variability observed in our records. Our findings also suggest a local SST response to solar influence of 0.62 °C (W/m²)^-1 for the 20th century which is similar to previously published global values of climate sensitivity for solar radiation.

 

 

Examples of a sclerosponge