Snow-albedo feedback and Swiss spring temperature trends

We quantify the effect of the snow-albedo feedback on Swiss spring temperature trends using daily temperature and snow depth measurements from six station pairs for the period 1961–2011. We show that the daily mean 2-m temperature of a spring day without snow cover is on average 0.4 °C warmer than one with snow cover at the same location. This estimate is comparable with estimates from climate modelling studies. Caused by the decreases in snow pack, the snow-albedo feedback amplifies observed temperature trends in spring. The influence is small and confined to areas around the upward-moving snow line in spring and early summer. For the 1961–2011 period, the related temperature trend increases are in the order of 3–7 % of the total observed trend.

ENSO representation in climate models: from CMIP3 to CMIP5

We analyse the ability of CMIP3 and CMIP5 coupled ocean–atmosphere general circulation models (CGCMs) to simulate the tropical Pacific mean state and El Niño-Southern Oscillation (ENSO). The CMIP5 multi-model ensemble displays an encouraging 30 % reduction of the pervasive cold bias in the western Pacific, but no quantum leap in ENSO performance compared to CMIP3. CMIP3 and CMIP5 can thus be considered as one large ensemble (CMIP3 + CMIP5) for multi-model ENSO analysis. The too large diversity in CMIP3 ENSO amplitude is however reduced by a factor of two in CMIP5 and the ENSO life cycle (location of surface temperature anomalies, seasonal phase locking) is modestly improved. Other fundamental ENSO characteristics such as central Pacific precipitation anomalies however remain poorly represented. The sea surface temperature (SST)-latent heat flux feedback is slightly improved in the CMIP5 ensemble but the wind-SST feedback is still underestimated by 20–50 % and the shortwave-SST feedbacks remain underestimated by a factor of two. The improvement in ENSO amplitudes might therefore result from error compensations. The ability of CMIP models to simulate the SST-shortwave feedback, a major source of erroneous ENSO in CGCMs, is further detailed. In observations, this feedback is strongly nonlinear because the real atmosphere switches from subsident (positive feedback) to convective (negative feedback) regimes under the effect of seasonal and interannual variations. Only one-third of CMIP3 + CMIP5 models reproduce this regime shift, with the other models remaining locked in one of the two regimes. The modelled shortwave feedback nonlinearity increases with ENSO amplitude and the amplitude of this feedback in the spring strongly relates with the models ability to simulate ENSO phase locking. In a final stage, a subset of metrics is proposed in order to synthesize the ability of each CMIP3 and CMIP5 models to simulate ENSO main characteristics and key atmospheric feedbacks.

Soft balancing in the Americas: Latin American opposition to U.S. intervention, 1898–1936

In the aftermath of the 2003 U.S.-led invasion of Iraq, scholars of international relations debated how to best characterize the rising tide of global opposition. The concept of “soft balancing” emerged as an influential, though contested, explanation of a new phenomenon in a unipolar world: states seeking to constrain the ability of the United States to deploy military force by using multinational organizations, international law, and coalition building. Soft balancing can also be observed in regional unipolar systems. Multinational archival research reveals how Argentina, Mexico, and other Latin American countries responded to expanding U.S. power and military assertiveness in the early twentieth century through coordinated diplomatic maneuvering that provides a strong example of soft balancing. Examination of this earlier case makes an empirical contribution to the emerging soft-balancing literature and suggests that soft balancing need not lead to hard balancing or open conflict.

Riparian shading controls instream spring phytoplankton and benthic diatom growth

Dissolved oxygen (DO) concentrations showed a striking pattern in a multi-year study of the River Enborne, a small river in SE England. In each of three years (2010-2012), maximum DO concentrations were attained in mid-April, preceded by a period of steadily increasing diurnal amplitudes, followed by a steady reduction in both amplitude and concentration. Flow events during the reduction period reduce DO to low concentrations until the following spring. Evidence is presented that this pattern is mainly due to benthic algal growth which is eventually supressed by the growth of the riparian tree canopy. Nitrate and silicate concentrations are too high to inhibit the growth of either benthic algae or phytoplankton, but phosphate concentrations might have started to reduce growth if the tree canopy development had been delayed. This interpretation is supported by evidence from weekly flow cytometry measurements and analysis of the diurnal, seasonal and annual patterns of nutrient concentrations. As the tree canopy develops, the river switches from an autotrophic to a heterotrophic state. The results support the use of riparian shading to help control algal growth, and highlight the risks of reducing riparian shade.

First-order-reversal-curve analysis of Pr-Fe-B-based exchange spring magnets

Ribbons of nominal composition (Pr(9.5)Fe(84.5)B(6))(0.96)Cr(0.01)(TiC)(0.03) were produced by arc-melting and melt-spinning the alloys on a Cu wheel. X-ray diffraction (XRD) reveals two main phases, one based upon alpha-Fe and the other upon Pr(2)Fe(14)B. The ribbons show exchange spring behavior with H (c) = 12.5 kOe and (BH)(max) = 13.6 MGOe when these two phases are well coupled. Transmission electron microscopy revealed the coupled behavior is observed when the microstructure consists predominantly of alpha-Fe grains (diameter similar to 100 nm.) surrounded by hard material containing Pr(2)Fe(14)B. The microstructure is discussed in terms of a calculation by Skomski and Coey. A first-order-reversal-curve (FORC) analysis was performed for both a well-coupled sample and a poorly coupled sample. The FORC diagrams show two strong peaks for both the poorly coupled sample and for the well-coupled material. In both cases, the localization of the FORC probability suggests magnetizing interactions between particles. Switching field distributions were calculated and are consistent with the sample microstructure.

Hopf Bifurcations in a Watt Governor with a Spring

This paper pursues the study carried out in [ 10], focusing on the codimension one Hopf bifurcations in the hexagonal Watt governor system. Here are studied Hopf bifurcations of codimensions two, three and four and the pertinent Lyapunov stability coefficients and bifurcation diagrams. This allows to determine the number, types and positions of bifurcating small amplitude periodic orbits. As a consequence it is found an open region in the parameter space where two attracting periodic orbits coexist with an attracting equilibrium point.

Spring into summer : a novel

Spring into Summer is a novel based on my experiences as a student living in London for a year. The central character, an American under-graduate student studying history, attempts to complete a piece of work by his older brother who is killed in a car accident several months prior to his brother's departure for England. The narrative traces the younger brother's efforts and eventual failure to work on the history; in so doing, he also fails to become more like his older brother whom he greatly loved and admired. Thus, a doppelganger, or "Double" of sorts is used. Most of the action of the novel is set in London. However, the main character also travels to Dublin, York, and several other places in the British Isles, thereby giving a more complete picture of the experiences an American student undergoes while living abroad. During a year which many people might see as an escape from the problems and pressures of everyday life, the central character is forced to undergo a painful process of self-examination, resulting in his reevaluation of himself, his priorities, and his ambitions.

Perspective: LaGuardia Community College Newsletter (Spring 1981)

Vol.9 No.1 Spring 1981; Perspective is a quarterly publication of LaGuardia Community College / CUNY which is designed and edited by the Office of Communications, Bill Freeland, director. Information on news and features stories should be addressed to the office In room M194. Faculty and staff news items should be sent to Dr. Roberta Matthews, Associate Dean of Faculty, room SB65.

Listing of Faculty Publications, Spring 1982

The Library Media Resources Center is happy to publish this revised Listing of Faculty Publications. As you recall, the first edition was issued in 1979 and so, 2 1/2 years later, it is our pleasure to present a larger and more complete edition... Special thanks to Professor Albert Talero who did all the editing and arrangements for the publication. Thanks also to Professor Fred Low for making the TRS-80 wordprocessing facilities of the LaGuardia Automated Library System (LALS) available for this edition. --Ngozi Agbim, April 23, 1982; 51 p.

Perspective: LaGuardia Community College Newsletter (Spring 1983)

Vol. 11 No.2; Perspective is a quarterly publication of LaGuardia Community College / CUNY which is designed and edited by the Office of Communications, Bill Freeland, director. Information on news and features stories should be addressed to the office In room M194. Faculty and staff news items should be sent to Dr. Roberta Matthews, Associate Dean of Faculty, room SB65.

Perspective: LaGuardia Community College Newsletter (Spring 1984)

Vol. 12 No.2; Perspective is a regular publication of LaGuardia Community College/CUNY which is designed and edited by the Office of Communications, Bill Freeland, director. Information on news and features stories, as well as faculty and staff notes, should be addressed to the office in room M413.

Listing of Faculty Publications, Spring 1985

The Library-Media Resources Center is pleased to present you with the most recent edition of the LaGuardia Listing of Faculty Publications. In it you will find proof of the vitality and commitment to scholarship of the LaGuardia Faculty. You will also see the diversity of interests and expertise of your colleagues…Thanks also to Dorothy Lopez and Eddie Greissle, who labored long hours at the microcomputer reaping this bumper crop of information. –Al Talero, April 10, 1985; 63 p.

Perspective: LaGuardia Community College Newsletter (Spring 1986)

Vol. 14 No.2; Perspective is a regular publication of LaGuardia Community College / CUNY which is designed and edited by the Office of Communications, Bill Freeland, director. Randy Fader-Smith is staff writer and photographer. Information for news and feature stories should be addressed to the office in room M413. Faculty and staff news items should be sent to Dr. Roberta Matthews, Associate Dean of Faculty, room M202.

Spring 2014

Inside this Issue: Friends Board Meets Baumgarte to SpeakInaugurations… — Dean HerringA Note From the Sec.- Treas. — Dr. FaulknerMember Application