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In recent years, large-scale tree mortality events linked to global change have occurred around the world. Current forest monitoring methods are crucial for identifying mortality hotspots, but systematic assessments of isolated or scattered dead trees over large areas are needed to reduce uncertainty on the actual extent of tree mortality. Here, we mapped individual dead trees in California using sub-meter resolution aerial photographs from 2020 and deep learning-based dead tree detection. We identified 91.4 million dead trees over 27.8 million hectares of vegetated areas (16.7-24.7% underestimation bias when compared to field data). Among these, a total of 19.5 million dead trees appeared isolated, and 60% of all dead trees occurred in small groups (≤ 3 dead trees within a 30 × 30 m grid), which is largely undetected by other state-level monitoring methods. The widespread mortality of individual trees impacts the carbon budget and sequestration capacity of California forests and can be considered a threat to forest health and a fuel source for future wildfires. Tree mortality due to climate change and other disturbances is on the rise. Here, the authors use high-resolution remote sensing data, ground observations and deep learning to quantify individual dead trees and potential drivers across California in the year 2020, encompassing 91.4 million dead trees. [ABSTRACT FROM AUTHOR]

Timber harvesting and related management practices associated with industrial timberlands have changed dramatically in the last two decades. Industrial timberlands are now more carefully assessed and mitigated. Recent studies of mass wasting in northern California included a review of historical aerial photographs from the early 1940s through 2016 and field measurements of nearly 3,000 shallow landslides on industrially managed timberlands. Significant improvements have been seen in management practices over time that include but are not limited to reduced harvest unit sizes, increased streamside tree retention, reduced road density, and improved road-building practices. These improvements are a result of a variety of sources such as evolving state regulations, voluntary conservation plans, and increased professional oversight. Subsequently, significant decreases in management-related erosion are being observed across the area included in this study. Observations show that improvements in management practices have positively affected regional mass wasting. In this investigation, significant changes have been noted in both causal mechanisms and landslide erosion rates. The study data shows that before the year 2000, nearly 85 percent of landslide-related erosion was determined to be the result of historical logging, either by harvesting or from roads (generally poor design and/or location). Shallow landslide erosion rates have varied over the duration of time reviewed for this study, peaking in the 1970s. Since 2000, erosion rates across the study area have decreased to 20 m3/km2/yr, which is a 92 percent reduction compared with the historical rate. [ABSTRACT FROM AUTHOR]

Drought contributed to extensive dieback of southern California chaparral, and normalized difference vegetation index before drought and near the end of the drought was used to estimate this dieback, after accounting for other disturbances recorded in aerial photographs. Within the perimeters of two megafires that occurred after the drought, the 2017 Thomas Fire and the 2018 Woolsey Fire, there had been extensive areas of dieback. Comparing dieback with Monitoring Trends in Burn Severity measures of fire severity, there was a highly significant negative relationship between drought‐caused shrub dieback and fire‐caused dieback as measured by fire severity. We interpret this as further support for our remote sensing methodology for prefire dieback. Models of fire behavior suggest that one means by which dieback contributes to fire size is through increasing the density and distance of spot fires, particularly under extreme wind conditions. Lower elevation chaparral associations appear to be most vulnerable and are closer to urban environments, which should be a concern to fire managers in regions subjected to extended droughts. [ABSTRACT FROM AUTHOR]

For each restoration project, it is essential to define a reference ecosystem towards which ecological restoration aims. Historical information may be useful in the construction of the reference model and in finding out about the type and degree of disturbances that have caused degradation on the site, as legacies of past human land-uses have been shown to be major determinants of vegetation and plant diversity even in the very long term. The aim of this paper is the retrace the history of three sites where restoration protocols were tested, to better apprehend the potential reference ecosystems as well as the disturbances that degraded them. To do so, we first compiled information on the reference ecosystems at the landscape scale. Then, we compiled historical and agricultural information at the scale of the sites from local historical documents, historical reviews and aerial photographs. The three sites most likely were grasslands or oak savannas before European settlement. Grasslands used to cover 8.9 million ha in California. They were species-rich grasslands managed with fire by the native people and grazed by native ungulates. Early settlers introduced cattle grazing and changed fire regimes. Later on, many grasslands were converted to cultivation. All three sites were used for ranching and sometimes overgrazed. At least two of them were cultivated, probably leading to restoration being harder there, as plowing eliminates perennial species, destroys the seedbank, changes soil characteristics. [ABSTRACT FROM AUTHOR]

Context: Increases in tree cover at dry forest margins are a global phenomenon. Yet, how pre-existing tree cover interacts with terrain and water balance to influence tree cover change is not well-understood, nor whether subsequent disturbances restore prior tree cover patterns or create novel patterns. Objectives: To assess how terrain, water balance and pre-existing patterns of tree cover influenced late twentieth century tree cover change, and how subsequent wildfires altered tree cover patterns. Methods: We analyzed tree canopy cover at four sites at the forest-steppe ecotone on the eastern side of the Sierra Nevada, California, U.S.A., using aerial photographs from 1953/1955, 1999/2002 and 2016. Influences on tree cover change were assessed using statistical modeling, and tree cover in 1953/1955 was compared with post-wildfire tree cover in 2016. Results: From 1953 to 2002, area with > 25% canopy cover increased by 1.5 to 5-fold and treeless area decreased by 17–111%. Mesic areas and areas of sparse tree cover close to existing forest tended to gain more canopy cover. Subsequent wildfires caused a mix of net tree cover loss, little change and gain relative to 1953/1955, but at all sites areas with > 25% cover and < 10% cover in 1953/55 experienced net losses and gains respectively by 2016. Conclusions: Accounting for initial tree cover and its configuration are crucial to assessing water balance and terrain effects on tree cover change. Our work highlights how wildfires can generate novel patterns of tree cover relative to historical baselines, especially following decades of fire exclusion. [ABSTRACT FROM AUTHOR]

A thread-leg shrimp, Nematocarcinus sp., was photographed at 870 m off the San Juan Seamount off California. The shrimp was not collected. The color pattern is very different from previously described northeastern Pacific species of Nematocarcinus. The image in the photograph is too distant to see characteristic details of the rostrum. A previous report of Nematocarcinus exilis (Spence Bate, 1888) from Oregon cannot be verified, so this is the first well-documented report of this family in the eastern Pacific north of Mexico. [ABSTRACT FROM AUTHOR]

Main Street is an indelible image in the American consciousness made hyperreal at Disneyland California in 1955. For subsequent parks in Tokyo and Paris, Disney recontextualized Main Street, but Hong Kong Disneyland’s version was formed as a copy of the California original. This copy demonstrates that transference of a structural form to a new cultural context is not a guarantee of the concomitant transmission of the originating culture’s sensory modality. The arising dissonant tension between the form (signifier) and substance (signified) of Hong Kong’s Main Street has led to its ongoing semiosis due to local cultural and corporate pressures. This paper presents a framework to analyze this dissonance and semiosis through comparison of external and internal photographs of the same eight landmarks at both parks. The problem of transferring meaning into a new cultural context for an international sign suggests Hong Kong’s Main Street could be the last that Disney constructs. [ABSTRACT FROM AUTHOR]

An essay is presented that analyzes photography of California's Occupy Los Angeles (OLA) movement, part of the broader Occupy Wall Street movement that emerged in 2011. It focuses on women, commenting on themes of women's antiracist interventions into the movement's rhetoric, women's responses to the masculinist space of the movement, and women's embodied political protest. The article adopts a transnational antiracist feminist perspective to analyze decolonial performances of resistance.

Objective: There is clinical heterogeneity among the autism spectrum disorders (ASD). The presence of dysmorphology (minor physical anomalies; MPAs) is one possible tool for defining a clinically relevant subset in ASD. This study employs an adaptation of Miles and Hillman’s (2000) classifications by using photographs to identify a subgroup with significant dysmorphology among children with ASD, typical development (TYP), and developmental delay (DD). Method: Children with ASD, DD, and TYP between 2 and 5 years old were part of the CHARGE Study. Pediatric specialists blinded to diagnostic group classified photographs based on the number of MPAs present: ‘dysmorphic’ if >3 and ‘nondysmorphic’ if <3 MPAs. Results: Photographs for 324 children were included. Significantly more children with ASD were classified as dysmorphic compared to TYP children (p = .007). In children with ASD, seizures were more prevalent in those rated dysmorphic (p = .005). Frequencies were similar between ASD versus DD (p = .19) after removing those with known syndromes. Conclusion: Photographic assessment can be used to detect generalized dysmorphology in children who are often difficult to examine. This has clinical relevance, as children with multiple MPAs can be identified through the use of photographs and prioritized for investigation of brain abnormalities and underlying genetic disorders. [ABSTRACT FROM PUBLISHER]

The article offers information on the works of artist Paul McCarthy in Pasadena, California. It mentions the workplace of Mccarthy as his hideaway for rehabilitation and plastic surgery with hyper-real scenarios, disgusting images and other visceral objects. It explains that his works sarcastically expose the Western mass media's impact on individual baring familial and social traumata.

This study focused on a spatial and temporal analysis of the active channel and associated floodplain lakes using aerial photographs spanning five decades (1942, 1962, 1985, 1999) over a 140 km long reach of the Sacramento. Planimetric changes were analysed longitudinally and temporally to highlight the spatial structures and their evolution through time. The results underline complex changes and space-time pattern in bank erosion, channel length and active channel width. The bank erosion and also channel lengthening were higher between 1962 and 1985 than in the two periods studied before and after. Active channel width significantly decreased from 1942 to 1999; partly progressively from upstream to downstream with local widening whatever the studied periods. Similarly the floodplain lakes observed before 1942-1962 were significantly different in size and geometry from those which appeared during the most recent period. The creation of lakes is less frequent after the 1940s, with a secondary peak of occurrence during the 1962-1985 period. The interpretation of these changes is complex because of various human pressures acting over different time scales (bank protection, flow diversion, sediment starvation, land-use changes) and various natural influences (flood sequences through out the period, geological setting). The findings are discussed by comparison with previous work, and highlight the important effect of dam impact on peak flow and sediment starvation modifying longitudinally hydraulic conditions within the channel, but also the increase in riprap protection which induced change in bank erosion, channel planimetry and floodplain lake characters (geometry, frequency of renewal). Variation in flood intensities is also observed as having positive effects on the bank erosion pattern. Secondarily, land-use changes also controlled bank erosion intensity. Copyright © 2010 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: The Million Trees LA initiative intends to improve Los Angeles''s environment through planting and stewardship of 1 million trees. The purpose of this study was to measure Los Angeles''s existing tree canopy cover (TCC), determine if space exists for 1 million additional trees, and estimate future benefits from the planting. High-resolution QuickBird remote sensing data, aerial photographs, and geographic information systems were used to classify land cover types, measure TCC, and identify potential tree planting sites. Benefits were forecast for planting of 1 million trees between 2006 and 2010, and their growth and mortality were projected until 2040. Two scenarios reflected low (17%) and high (56%) mortality rates. Numerical models were used with geographic data and tree size information for coastal and inland climate zones to calculate annual benefits and their monetary value. Los Angeles''s existing TCC was 21%, and ranged from 7 to 37% by council district. There was potential to add 2.5 million additional trees to the existing population of approximately 10.8 million, but only 1.3 million of the potential tree sites are deemed realistic to plant. Benefits for the 1-million-tree planting for the 35-year period were $1.33 billion and $1.95 billion for the high- and low-mortality scenarios, respectively. Average annual benefits were $38 and $56 per tree planted. Eighty-one percent of total benefits were aesthetic/other, 8% were stormwater runoff reduction, 6% energy savings, 4% air quality improvement, and less than 1% atmospheric carbon reduction. [Copyright &y& Elsevier]

The article explores the works of photographer David Bacon, particularly the photographs of the organizing effort and strike of low-wage, immigrant workers in the hotel industry of San Francisco, California in 2004. An overview of the career of Bacon is provided, along with a commendation on the educational significance of his works. The author summarizes the areas where Bacon's work is found to be relevant to anthropological commitments and practice.

Abstract: Natural landscapes are increasingly subjected to impacts associated with urbanization, resulting in loss and degradation of native ecosystems and biodiversity. Traditional classification approaches to the characterization of urbanization may prove inadequate in some human-modified landscapes where complex and unique combinations of conditions can make classification and delineation of patches difficult. We describe a model that depicts existing human development as a fine-grained continuous variable using parcel-based land use data and transportation networks. We derived percent development values across our 88000-ha study area, the Lake Tahoe basin. Our modeled values were highly correlated with observed levels of development based on high-resolution aerial photographs. We demonstrate how our model of development can be used to address practical conservation questions by evaluating the potential effects of highly interspersed urban land development and wildland conditions on the amount and availability of habitat suitable for the resident California spotted owl (Strix occidentalis occidentalis) at two points in time (current and 40 years in the future). The results indicated that assessments not accounting for the indirect effects of development may overestimate the amount of available habitat by 19–83%. Portraying urbanization as a continuum across entire landscapes captured fine-grained landscape complexity at scales that were relevant to the habitat needs and environmental sensitivities of a species of conservation interest. This relatively simple approach should aid ecologists and landscape planners in evaluating the current or future effects of urbanization on ecological elements and processes. [Copyright &y& Elsevier]

This paper seeks to shed new light on the much-discussed survey work of American photographic pioneer Timothy H. O'Sullivan through a close analysis of a hitherto unnoticed collection of King Survey photographs at the University of California's Bancroft Library. Among the notable features of this collection is the appearance, in seven rare views of Eastern California, of a ‘T.H.O'S.’ monogram, as well as the existence of a double set of captions, the one more serious or official, the other more informal and sometimes quite humorous. These features, along with the eastward orientation of the collection and the particular selections of images inserted in the collection's opening and closing sequences, suggest a narrational reading of the set that tends to displace, or at least to redefine, traditional arguments about O'Sullivan's oeuvre in relation to the institutional demands of his employers. The double hypothesis of a humorous and narrational reading embodied in the collection in turn suggests new ways of interpreting the many narrative or reflexive bits contained in O'Sullivan's Western photographs. [ABSTRACT FROM AUTHOR]

An empirical comparison of the EO-1 Hyperion, EOS ASTER, and Landsat ETM sensors was performed to examine the utility of these three sensors for gold-associated lithologic mapping in the southeastern Chocolate Mountains area, California. Three images were evaluated with respect to three aspects: classification accuracy, matched filtering score index, and separability of the five significant rock types in the study area. The results show that the classifications from Hyperion and ASTER data are mostly similar with an overall accuracy of over 85 percent and kappa coefficient 0.81. Due to the presence of more SWIR and thermal bands, the Hyperion and ASTER images can achieve better lithologic mapping than ETM. The assessment of matched filtering score index and the separability also supports these findings. Hyperion can discriminate more similar classes than ASTER and ETM, while the better availability and spatial coverage makes the ASTER sensor more suitable for large-area lithologic mapping. [ABSTRACT FROM AUTHOR]

The land-use history of an ecosystem influences current structure and possibly response to modern disturbances and stresses. In semiarid systems the nature of land-use legacies is poorly understood, confounding efforts to establish sustainable management approaches. We compare previously cultivated and non-cultivated lands in Owens Valley, California, where cultivation once extended to 34% of the valley floor but was largely discontinued by 1940, to measure the influence of past disturbance on modern vegetation. We combined historic maps of cultivated and non-cultivated land with an extensive vegetation survey, historic aerial photographs, and satellite measurements of vegetation response to precipitation variability to examine the importance of land-use history in determining the sensitivity of vegetation to annual variations in precipitation. Remote sensing analysis showed that total plant cover on previously cultivated lands was lower and fluctuations in cover were marginally more dependent on precipitation compared with plant cover on non-cultivated lands. We then compared modern plant assemblages within cultivated and non-cultivated land to determine if compositional differences could explain the current patterns of vegetation cover. We found lower species richness on previously cultivated parcels, and higher frequency and cover of perennial grasses on non-cultivated lands. Therefore, we showed differences in land-cover patterns, isolated a mechanism that could account for the differences (species differences), and developed a method for remotely analyzing land regions that have experienced historic anthropogenic disturbance. [ABSTRACT FROM AUTHOR]

This article focuses on the strange performance of an untethered photograph arrived at the house of a Vietnamese refugee family in Linda Vista, California. It is a picture of the Vietnamese grandparents. The picture appears at a moment when the family, alter its displacement in the aftermath of the Vietnam War, seems more settled. The photograph is most often discussed in terms of two by canonical concerns: reference and time.

Natural color photographs were used to detect the coverage of saltcedar, Tamarix parviflora, along a 40 km portion of Cache Creek near Woodland, California. Historical aerial photographs from 2001 were retrospectively evaluated and compared with actual ground-based information to assess accuracy of the assessment process. The color aerial photos were sequentially digitized, georeferenced, classified using color and texture methods, and mosaiced into maps for field use. Eight types of ground cover ( Tamarix, agricultural crops, roads, rocks, water bodies, evergreen trees, non-evergreen trees and shrubs (excluding Tamarix)) were selected from the digitized photos for separability analysis and supervised classification. Due to color similarities among the eight cover types, the average separability, based originally only on color, was very low. The separability was improved significantly through the inclusion of texture analysis. Six types of texture measures with various window sizes were evaluated. The best texture was used as an additional feature along with the color, for identifying Tamarix. A total of 29 color photographs were processed to detect Tamarix infestations using a combination of the original digital images and optimal texture features. It was found that the saltcedar covered a total of 3.96 km2 (396 hectares) within the study area. For the accuracy assessment, 95 classified samples from the resulting map were checked in the field with a global position system (GPS) unit to verify Tamarix presence. The producer's accuracy was 77.89%. In addition, 157 independently located ground sites containing saltcedar were compared with the classified maps, producing a user's accuracy of 71.33%. [ABSTRACT FROM AUTHOR]

This essay analyses Stanford's sponsorship of Muybridge's early instantaneous photographs of animals in motion in the context of the United States' complex and troubled process of mechanisation during the late nineteenth century. In short, I contend that the railroad executive Stanford and his advocates staged and disseminated these photographs in order to consolidate, promote, and naturalise the developments of industrial capitalism. The railroad executive proffered these experiments as evidence of his commitment to the public good, as clear benefits for both the economy in general and the art community in particular, and as exemplars of the new industrial order. At the same time, many contemporaries on both sides of the Atlantic responded to these photographs by renewing heated, ongoing controversies over the role and nature of technology, industrialism, and corporate plutocrats like Stanford. Antagonists often rejected the stills' highly touted social utility and Stanford's proclaimed munificence. But because these were photographs, the debate centred on distinct modes and philosophies of visual production and consumption. The Muybridge archive, and responses thereto, thus marked an important moment when two conceptual systems of viewership collided. At stake, ultimately, was the ability to lay claim to social authority through the very practice of representation. [ABSTRACT FROM AUTHOR]

Discusses the news items and photographs published by the "Los Angeles Times" about the Watts Rebellion sparked by the arrest of Marquette Frye, an African American man stopped by police officers for speeding in California on August 12, 1965. Involvement of a crowd in the incident; Increase in military violence in the U.S. in 1965; Article about a policeman injured during the riot; Bias showed by the periodical regarding the riot; Evidences showed by the United Press International regarding police brutality.

Presents photographs of farm workers in California.

On 28 August 2002, a visually striking sequence of events appeared in satellite imagery showing a coastally trapped disturbance (CTD) propagating northward along the coast of California against a northerly background flow. As a narrow tongue of coastal stratus indicative of the CTD propagated northward, a long, linear set of wave clouds developed ahead of the advancing CTD and angled away from the coast. The CTD and cloud lines moved northward over the next ∼6 h and, as they approached Cape Mendocino (CM), the leading edge of the CTD clouds rolled up into a cyclonic mesoscale eddy—with the wave clouds being wrapped into the eddy. The CTD abruptly stalled and failed to round CM. Further, a second cyclonic mesoscale eddy formed southwest of Point Arena (PA). Although there has been extensive study of the propagation phase of CTDs, relatively little attention has been paid to the cessation of their propagation wherein mesoscale eddy development is not uncommon. Using the U.S. Navy's Coupled Ocean–Atmosphere Mesoscale Prediction System (COAMPS), run in an operational manner, numerous observed features of this case are forecast, including: (i) the cold, shallow, cloud-filled, northward-propagating CTD; (ii) the development, linear structure, orientation, and movement of an oblique hydraulic jump–like (“shock”) feature; (iii) a southerly wind shift associated with the CTD that precedes the advancing cloud tongue by several hours in both the observations and the model; (iv) the modeled CTD that rounds PA, but fails to round CM; and (v) the formation of modeled cyclonic mesoscale eddies near both CM and PA. North of PA, however, a phase error develops in which the modeled CTD propagation is too slow. The model forecast cloud tongue behaves as a gravity current, and similar to earlier observational and modeling studies of CTDs, the model forecasts a bore propagating in the stratified atmosphere immediately above the marine boundary layer. Supercritical flow is forecast in the accelerating northerly flow rounding CM, and when the advancing bore interacts with this high Froude number region a pronounced oblique shock develops and the CTD stalls. Vorticity is enhanced along this shock due to vertical stretching and potential vorticity is generated within the shock. Additionally, juxtaposition of the CTD's southerly flow with the background northerly flow creates a vortex sheet–like shear zone along the offshore flank of the CTD, with the horizontal gradient of absolute vorticity changing signs, which is a necessary condition for classic barotropic instability. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to evaluate spatial resolution effects on image classification. Classification maps were generated with a maximum likelihood (ML) classifier applied to three multi-spectral bands and variance texture images. A total of eight urban land use/cover classes were obtained at six spatial resolution levels based on a series of aggregated Colour Infrared Digital Orthophoto Quarter Quadrangle (DOQQ) subsets in urban and rural fringe areas of the San Diego metropolitan area. The classification results were compared using overall and individual classification accuracies. Classification accuracies were shown to be influenced by image spatial resolution, window size used in texture extraction and differences in spatial structure within and between categories. The more heterogeneous are the land use/cover units and the more fragmented are the landscapes, the finer the resolution required. Texture was more effective for improving the classification accuracy of land use classes at finer resolution levels. For spectrally homogeneous classes, a small window is preferable. But for spectrally heterogeneous classes, a large window size is required. [ABSTRACT FROM AUTHOR]

Speculates about the meanings the California Grizzly Giant sequoia tree photographs of Carleton Watkins might have communicated to their viewers. Investigation on the full-scale image that shows the height of the tree and a section that emphasizes its girth; Explanation on Watkin's understanding of a correct depiction of landscape; Reason the stature of the Grizzly Giant was diminishing over time, according to the 1907 book of Galen Clark.

Like many parents in the US, teen mothers regularly have professional portraits taken of their children. This article, based on an ethnographic study of a diverse group of teen mothers in urban California, analyzes these baby pictures as representations of childhood, motherhood and family, and as material objects used in the construction of kin networks. Through these portraits teen mothers construct themselves as good mothers, resisting public denunciations of their childbearing at the same time that they embrace consumer culture. Small photos are exchanged with their friends and family members, contributing to a culture of care, albeit one based on market principles. [ABSTRACT FROM AUTHOR]

Abstract: Tree canopy cover data from aerial photographs and building energy simulations were applied to estimate energy savings from existing trees and new plantings in California. There are approximately 177.3 million energy-conserving trees in California communities and 241.6 million empty planting sites. Existing trees are projected to reduce annual air conditioning energy use by 2.5% with a wholesale value of $ 485.8 million. Peak load reduction by existing trees saves utilities 10% valued at approximately $778.5 million annually, or $ 4.39/tree. Planting 50 million trees to shade east and west walls of residential buildings is projected to reduce cooling by 1.1% and peak load demand by 4.5% over a 15-year period. The present wholesale value of annual cooling reductions for the 15-year period is $ 3.6 billion ($ 71/tree planted). Assuming total planting and stewardship costs of $ 2.5 billion ($ 50/tree), the cost of peak load reduction is $ 63/kW, considerably less than the $ 150/kW benchmark for cost-effectiveness. Influences of tree location near buildings and regional climate differences on potential energy savings are discussed. [ABSTRACT FROM AUTHOR]

Highlights Marc Rader's photo-essay on California gated communities. Architectural design; Design themes; Functionality.

Presents photographs of different alleys and houses in Los Angeles, California, taken in October 1976.

The author reflects on the photographer's ability to capture the images of ordinary places in articulate manner. He states that photographing a place is not a matter of duplicating the image of the subject, but the ability of the photographer to put color and bring out the importance of the subject that is usually disregarded. He opines that a photographer must prove that his camera is capable in capturing his subject of passion. Several photographs of the places in the Presidio of San Francisco are presented including a picture of "Trail Fork," "Cypress Triad," and "Common Ground."