No description available.

Thesis: S.M., Joint Program in Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Department of Mechanical Engineering; and the Woods Hole Oceanographic Institution), 2013. / Includes bibliographical references (pages 133-141). / Between 2002 and 2011 a single mooring was maintained in the core of the Pacific Water boundary current in the Alaskan Beaufort Sea near 152° W. Using velocity and hydrographic data from six year-long deployments during this time period, we examine the interannual variability of the current. It is found that the volume, heat, and freshwater transport have all decreased drastically over the decade, by more than 80%. The most striking changes have occurred during the summer months. Using a combination of weather station data, atmospheric reanalysis fields, and concurrent shipboard and mooring data from the Chukchi Sea, we investigate the physical drivers responsible for these changes. It is demonstrated that an increase in summertime easterly winds along the Beaufort slope is the primary reason for the drop in transport. The intensification of the local winds has in turn been driven by a strengthening of the summer Beaufort High in conjunction with a deepening of the summer Aleutian Low. Since the fluxes of mass, heat, and freshwater through Bering Strait have increased over the same time period, this raises the question as to the fate of the Pacific water during recent years and its impacts. We present evidence that more heat has been fluxed directly into the interior basin from Barrow Canyon rather than entering the Beaufort shelfbreak jet, and this is responsible for a significant portion of the increased ice melt in the Pacific sector of the Arctic Ocean. / by Eric T. Brugler. / S.M.

Thesis (Ph. D. in Physical Oceanography)--Joint Program in Physical Oceanography (Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2013. / Cataloged from PDF version of thesis. / Includes bibliographical references (p. 259-275). / Two high-resolution mooring arrays extending from the outer shelf to the mid continental slope are used to elucidate shelf-basin exchange at the inflow to and the outflow from the Arctic Ocean. Pacific Water entering the Arctic Ocean forms the Western Arctic shelfbreak current along the Beaufort Sea slope. Data from the mooring array at 152°W-approximately 150 km east of Pt. Barrow, AK-reveals that this current has two distinct states in summer depending on the water mass it transports. When advecting Alaskan Coastal Water it is surface-intensified and both baroclinically and barotropically unstable. This configuration lasts about a month with an average transport of 0.7 Sv. When advecting Chukchi Summer Water the current is bottom-intensified and is only baroclinically unstable. This state also exists for approximately a month with an average transport of 0.6 Sv. The strong mean-to-eddy energy conversion causes both configurations of the current to spin down over a distance of a few hundred kilometers, suggesting that warm Pacific Water does not enter the Canadian Arctic Archipelago via this route. Dense water formed in the Nordic Seas overflows the Denmark Strait and undergoes vortex stretching, forming intense cyclones that propagate along the East Greenland slope. Data from the mooring array at 65°N-roughly 300 km downstream of Denmark Strait-was used to determine the full water column structure of the cyclones. On average a cyclone passes the array every other day in the vicinity of the 900 m isobath, although the depth range of individual cyclones ranges between the 500 m and 1600 m isobaths. The cyclones self-propagate at 0.45 m/s and are also advected by the mean flow of 0.27 m/s, resulting in a total propagation speed of 0.72 m/s. They have a peak azimuthal speed of 0.22 m/s at a radius of 7.8 km and contain overflow water in their core. In the absence of the cyclones, the background flow is dominated by the East Greenland Spill Jet. This is shown to be a year-round feature transporting 2-4 Sv of dense water equatorward along the upper continental slope. / by Wilken-Jon von Appen. / Ph.D.in Physical Oceanography

A thesis presented in fulfilment of the requirements for the degree of doctor o philosophy August 1977 / P a r t 1 o f t h i s w o r k p r o v i d e s a b r o a d o v e r v i e w a n d , w h e r e p o s s i b l e , a q u a n t i t a t i v e a s s e s s m e n t o f t h e c o m p l e x p h y s i c a l p r o c e s s e s w h i c h t o g e t h e r c o n s t i t u t e t h e m e c h a n i s m o f n u c l e a t e b o i l i n g h e a t t r a n s f e r . I t i s s h o wn t h a t u n d e r a w i d e r a n g e o f c o n d i t i o n s t h e p r i m a r y s u r f a c e - t o - 1 i q u i d h e a t f l o w s w i t h i n a n a r e a o f b u b b l e i n f l u e n c e a r c s o r e d i s t r i b u t e d a s t o m a n i f e s t t h e m s e l v e s p r e d o m i n a n t l y a s l a t e n t h e a t t r a n s p o r . t h a t i s , a s v a p o r i s a t i o n i n t o a t t a c h e d b u b b l e s . T h i s a n d r e l a t e d f i n d i n g s a r e a p p l i e d i n t h e d e r i v a t i o n o f a new p o o l b o i l i n g h e a t t r a n s f e r c o r r e l a t i o n . The c o r r e l a t i o n a l l o w s t h e p r e d i c t i o n o f b o i l i n g c u r v e s ( q / A v , r s u s AT) a t a n y p r e s s u r e p r o v i d e d t h a t o n e b o i l i n g c u r v e f ' . t h e s ame s u r f a c e - l i q u i d c o m b i n a t i o n i s . a v a i l a b l e u s a r c f r e n c e . P a r t 2 d e a l s i n g r e a t e r d e t a i l w i t h o n e o 1 t h e c o m p o n e n t p r o c e s s e s o f l a t e n t h e a t t r a n s p o r t , n a m e l y m i c r o l a y e r e v a p o r a t i o n . A l i t e r a t u r e r e v i e w r e v e a l s t h e n e e d f o r s y n c h r o n i s e d r e c o r d s o f m i c r o l a v e r g e o m e t r y v e r s u s t i m e a n d o f n o r m a l b u b b l e g r o w t h a n d d e p a r t u r e . An a p p a r a t u s d e v e l o p e d t o p r o v i d e s u c h r e c o r d s i s d e s c r i b e d . H i g h - s p e e d c i n e i n t e r f e r e n c e p h o t o g r a p h y f r o m b e n e a t h a n d t h r o u g h a t r a n s p a r e n t h e a t i n g s u r f a c e p r o v i d e d d e t a i l s o f m i c r o l a v e r g e o m e t r y a n d a n i m a g e - r e f l e c t i o n s y s t e m s y n c h r o n i s e d t h e s e r e c o r d s w i t h t h e b u b b l e p r o f i l e v i e w s . R e s u l t s a r e g i v e n f o r m e t h a n o l a n d e t h a n o l be t l i n g a t s u b a t m o s p h e r i c p r e s s u r e s a n d a t v a r i o u s h e a t • : . . x e s a n d b u l k s u b c o o l i n v c . In a l l c a s e s i t i s f o u n d t h a t m i c r o l a y e r s w e r e o f s u b - m i c r o n t h i c k n e s s , t h a t m i c r o l a y e r t h i n n i n g w a s r e s t r i c t e d t o t h e i n n e r l a y e r e d g e ( w i t h t h e t h i c k n e s s e l s e w h e r e r e m a i n i n g c o n s t a n t o r i n c r e a s i n g w i t h t i m e ) a n d t h a t t h e c o n t r i b u t i o n o f t h i s v i a i b l c e v a p o r a t i o n t o t h e t o t a l v a p o u r f l o w i n t o b u b b l e s wa s n e g l i g i b l e . T h e o b s e r v a t i o n o f t h i c k e n i n g t o w a r d s t h e o u t e r m i c r o l a y e r e d g e , h o w e v e r , d e m o n s t r a t e s t h a t a l i q u i d r e p l e n i s h m e n t f l o w o c c u r r e d s i m u l t a n e o u s l y w i t h t h e e v a p o r a t i o n p r o c e s s . T h e e f f e c t s o f s u c h r e p l e n i s h m e n t a r c i n v e s t i g a t e d b y me a n s o f a n u m e r i c a l a n a l y s i s o f m i c r o l a y c r h e a t t r a n s f e r . T h e a n a l y s i s i n d i c a t e s t h a t t h e n e t e v a p o r a t i o n f r o m t h e c o n t i n u o u s l y r e p l e n i s h e d m i c r o l a y c r s wa s a s i g n i f i c a n t c o n t r i b u t o r t o t h e t o t a l b u b b l e g r o w t h . Th e o p t i c a l r e s u l t s o f t h e p r e s e n t s t u c y a r e t h u s r e c o n c i l e d w i t h t h e d e d u c t i o n s o f p u b l i s h e d s u r f a c e - t h c r m o m c t r y s t u d i e s . T h e f o r c e s a c t i n g on t h e o b s e r v e d b u b b l e s a r c a n a l y s e d a n d a r c f o u n d t o b e c o m p a t i b l e w i t h a r e p l e n i s h m e n t m e c h a n i s m . M i c r o l a y e r i n t c r f c r o m e t r y s t u d i e s f o u n d e d on p u b l i s h e d p o r t i o n s o f t h e p r e s e n t s t u d y a r c d i s c u s s e d a n d c o n t r o v e r s i a l r e s u l t s a n a l y s e d . /

Marburg, Med. Diss. v. 3. Nov. 1927.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 1996. / Includes bibliographical references (leaves 57-58). / by William James Williams. / M.S.

No description available.

Om binär kod, vävda bilder och Vǫluspá.

Thesis: Ph. D., Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Department of Earth, Atmospheric, and Planetary Sciences; and the Woods Hole Oceanographic Institution), 2017. / Cataloged from PDF version of thesis. / Includes bibliographical references. / Key players in the marine carbon cycle are the ocean-dwelling microbes that fix, remineralize, and transform organic matter. Many of the small organic molecules in the marine carbon pool have not been well characterized and their roles in microbial physiology, ecological interactions, and carbon cycling remain largely unknown. In this dissertation metabolomics techniques were developed and used to profile and quantify a suite of metabolites in the field and in laboratory experiments. Experiments were run to study the way a specific metabolite can influence microbial metabolite output and potentially processing of organic matter. Specifically, the metabolic response of the heterotrophic marine bacterium, Ruegeria pomeroyi, to the algal metabolite dimethylsulfoniopropionate (DMSP) was analyzed using targeted and untargeted metabolomics. The manner in which DMSP causes R. pomeroyi to modify its biochemical pathways suggests anticipation by R. pomeroyi of phytoplankton-derived nutrients and higher microbial density. Targeted metabolomics was used to characterize the latitudinal and vertical distributions of particulate and dissolved metabolites in samples gathered along a transect in the Western Atlantic Ocean. The assembled dataset indicates that, while many metabolite distributions co-vary with biomass abundance, other metabolites show distributions that suggest abiotic, species specific, or metabolic controls on their variability. On sinking particles in the South Atlantic portion of the transect, metabolites possibly derived from degradation of organic matter increase and phytoplankton-derived metabolites decrease. This work highlights the role DMSP plays in the metabolic response of a bacterium to the environment and reveals unexpected ways metabolite abundances vary between ocean regions and are transformed on sinking particles. Further metabolomics studies of the global distributions and interactions of marine biomolecules promise to provide new insights into microbial processes and metabolite cycling. / by Winifred M. Johnson. / Ph. D.

Sumario: Análisis de mercado; Análisis técnico; Análisis administrativo; Análisis legal y social; Análisis económico y financiero; Análisis de riesgo y sensibilidad; Anexos.