Re-calibration of Arctic sea ice extent datasets using Arctic surface air temperature records

A new seasonal and annual dataset describing Arctic sea ice extents for 1901–2015 was constructed by individually re-calibrating sea ice data sources from the three Arctic regions (North American, Nordic and Siberian) using the corresponding surface air temperature trends for the pre-satellite era (1901–1978), so that the strong relationship between seasonal sea ice extent and surface air temperature observed for the satellite era (1979-present) also applies to the pre-satellite era. According to this new dataset, the recent period of Arctic sea ice retreat since the 1970s followed a period of sea ice growth after the mid-1940s, which in turn followed a period of sea ice retreat after the 1910s. Arctic sea ice is a key component of the Arctic hydrological cycle, through both its freshwater storage role and its influence on oceanic and atmospheric circulation. Therefore, these new insights have significance for our understanding of Arctic hydrology.

EDITOR D. Koutsoyiannis

ASSOCIATE EDITOR not assigned     

A comparison of vector magnetograms from the marshall space flight center and mees solar observatory

We compare completely independent vector magnetic field measurements from two very different polarimetric instruments. The Marshall Space Flight Center's imaging vector magnetograph is based on a birefringent filter, routinely measuring all four Stokes parameters integrated over the filter bandpass (1/8 Å) which is tunable across the Fei 5250 line in 10 mÅ steps. The Haleakala Stokes Polarimeter of the Mees Solar Observatory (MSO) is based on a spectrometer, routinely measuring all four Stokes parameters of the Fei 6302.5 line simultaneously and then spatially scanning to build up a vector magnetogram. We obtained active region magnetic field data with both the Marshall Space Flight Center (MSFC) and MSO systems on five days during June 1985. After interpolating the MSFC vector fields onto the more coarse spatial grid of MSO we make a point-by-point comparison of the two vector fields for data obtained on two of these days (June 8 and 9). From this comparison we conclude: (1) the spatially-averaged line-of-sight components agree quite well; (2) although the MSO spatial grid is coarser, the quality of the MSO image is better than that of the MSFC data because of better seeing conditions; (3) the agreement between the transverse magnitudes is affected by the poor image quality of the MSFC data; and (4) if the effects of Faraday rotation caused by including line-center linear polarization in the method of analysis are taken into account, the azimuths show good agreement within the scatter in the data caused by the averaging process.National Research Council Resident Research Associate.     

Children in disasters: the role of household preparedness

To increase children’s resilience to disasters, it is important to expand our understanding of what increases their vulnerability. One household factor that has been tied to disaster resilience in general is the extent to which households have prepared themselves. In the context of wildfire preparedness, the current study examined whether households with very young, young, or teenage children differ in the extent to which they prepare their household compared to childless households. A two-wave survey study amongst Australian residents of wildfire-prone areas (N _wave1 = 998, N _wave2 = 514) found that households with young (under twelve years old) and very young (under six years old) children had prepared their properties less for wildfires compared to childless households at the start of the wildfire season, but they had caught up in property preparedness by the end of it. However, households with younger children also performed fewer disaster-planning actions than childless households. This difference remained significant throughout the season. The former group also reported lower motivation to prepare, greater perceived difficulty in preparing, and greater lack of time to prepare than childless households. The majority of these findings were explained by the younger age of the adult parents rather than the presence of younger children per se. An exception was that those with young and very young children reported a greater lack of time to prepare than childless adults of a similar age. We discuss practice and public policy implications that follow from this research.     

Mineral and fluid thermobarometry within the Variscan shearzone of Monteferro-El Rosal (NW Galicia, Spain): a preliminary investigation

The Monteferro El Rosal shear zone is characterized by an intense ductile deformation produced during the third phase of the Variscan orogeny. The petrology of the metasediments and the study of the fluid inclusions from synkinematic andalusite-bearing quartz veins indicate that the major Variscan phase of deformation occurred at around 2. 5–4 kbar and 565 ± 25°C.     

Community readiness for a new tsunami warning system: quasi-experimental and benchmarking evaluation of a school education component

Youth preparedness for disasters is a growing area of research. However, studies to date have relied on cross-sectional, correlational research designs. The current study replicated aspects of the one other study to date that has used a quasi-experimental strategy to evaluate youth preparedness for disasters. This study evaluated whether children were more knowledgeable and prepared for hazards generally but also in more specific relation to the rollout of a new tsunami warning system. Using a pretest–posttest with benchmarking design, the study found that following a brief school education program, supplementing a larger community-wide effort, children reported significant gains in preparedness indicators including increased knowledge as well as increases in physical and psychosocial preparedness. Within group effect sizes compared favorably with those from the previous experimental study in this area used to benchmark current intervention-produced findings and produced hints that combining school education programs with larger community preparedness efforts can enhance preparedness. Given that this is only one of two experimentally-based studies in an area of research largely dominated by cross-sectional designs, future research should consider the use of experimental designs, including those that are pragmatic and fit with needs of the school. The current approach has limitations that need to be considered. However, it also has some real advantages, including being used more extensively in fieldwork studies that evaluate various types of interventions. Through increased use of experimental design strategies, researchers can then also have increased confidence that educational programs are the source of increases in disaster resilience in youth and their families.     

The 2010/2011 Canterbury earthquakes: context and cause of injury

The aim of this study was to investigate causes of injury during the 2010/2011 Canterbury earthquakes. Data on patients injured during the Darfield (4 September 2010) and Christchurch (22 February 2011) earthquakes were sourced from the New Zealand Accident Compensation Corporation. The total injury burden was analyzed for demography, context of injury, causes of injury, and injury type. Injury context was classified as direct (shaking of the primary earthquake or aftershocks causing unavoidable injuries), action (movement of person during the primary earthquake or aftershocks causing potentially avoidable injuries), and secondary (cause of injury after shaking ceased). Nine categories of injury cause were identified. Three times as many people were injured in the Christchurch earthquake as in the Darfield earthquake (7,171 vs. 2,256). The primary shaking caused approximately two-thirds of the injuries from both quakes. Actions during the primary shaking and aftershocks led to many injuries (51.3 % Darfield and 19.4 % Christchurch). Primary direct caused the highest proportion of injuries during the daytime Christchurch quake (43.6 %). Many people were injured after shaking stopped in both events: 499 (22.1 % Darfield) and 1,881 (26.2 % Christchurch). Most of these people were injured during clean-up (320 (14.2 %) Darfield; 622 (8.7 %) Christchurch). In both earthquakes, more females than males (1,453 vs. 803 Darfield; 4,646 vs. 2,525 Christchurch) were injured (except by masonry, damaged ground, and during clean-up); trip/fall (27.9 % Darfield; 26.1 % Christchurch) was the most common cause of injury; and soft tissue injuries (74.1 % Darfield; 70.4 % Christchurch) was the most common type of injury. This study demonstrated that where people were and their actions during and after earthquakes influenced their risk of injury.     

Correlates of hazards education for youth: a replication study

Youth and families have been identified as particularly vulnerable to the effects of hazardous events. This study examined correlates of hazards education involvement for youth. Participants were 407 youth between the ages of 7 and 18 who filled out several indices reflecting hazards awareness, risk perceptions, psychological factors, knowledge, and adoption of hazards adjustments and family emergency plans. Additionally, interactive factors were assessed, the extent to which education programs encouraged youth to discuss their learning with parents and whether such discussions occurred. Overall, findings replicated and extended previous research. First, younger children were generally seen to be more prepared; girls, more knowledgeable. Second, youth involved in education programs had significantly higher levels of correct knowledge of readiness and response behaviors, lower levels of incorrect knowledge, and reported more home-based hazards adjustments. One important area where no differences were seen was in the area of family emergency planning. Predictors of increased educational benefits included program recency, encouragement to interact with parents and, to a slightly lesser extent, parent discussion willingness. Combined with previous research indicating that even simple and brief reading and discussion programs can produce tangible benefits, findings here encourage the incorporation of easy-to-do features that can increase benefits for youth and their families.