Igor Esau

Igor Esau
UiT The Arctic University of Norway

Ph.D. in meteorology
Research on local climate, planetary boundary layers, modeling Teaching meteorology and climate for students in energy

About

191
Publications
59,317
Reads
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4,537
Citations
Citations since 2016
64 Research Items
2822 Citations
20162017201820192020202120220100200300400500
20162017201820192020202120220100200300400500
20162017201820192020202120220100200300400500
20162017201820192020202120220100200300400500
Introduction
My primary scientific interest is to investigate links between small scale and global scale processes. Specifically, I focus on understanding on the role played by the stably stratified boundary layers in regulating the air quality, micro-climate and connections between the large-scale circulation and micro-physics of the Earth's Climate System.
Additional affiliations
August 2016 - November 2021
University of Bergen
Position
  • Professor
Description
  • Lecture course on Environment, Energy, and Climate
April 2003 - November 2021
Nansen Environmental and Remote Sensing Center
Position
  • Research Director
Description
  • Coordination of research activities in the group
March 1999 - March 2003
Uppsala University
Position
  • PhD Student

Publications

Publications (191)
Article
Full-text available
Cold environment supports a large diversity of local climates. Among them, urban climates in northern cities stand out for their pronounced warm temperature anomaly known as the Urban Heat Island (UHI). UHI in northern cities has been already studies through satellite images and in-situ observations in the urban canopy layer (UCL). Yet, the vertica...
Article
Full-text available
Forecast errors in near-surface temperatures are a persistent issue for numerical weather prediction models. A prominent example is warm biases during cloud-free, snow-covered nights. Many studies attribute these biases to parametrized processes such as turbulence or radiation. Here, we focus on the contribution of physical processes to the nocturn...
Conference Paper
Full-text available
В сборнике представлены материалы международного симпозиума «Связь климатических изменений с изменениями биологического и ландшафтного разнообразия Арктики и Субарктики» (г. Салехард, 2-3 декабря 2021 г.), в котором приняли участие более 50 исследователей из 24 научных и научно-образовательных организаций России, Финляндии, Норвегии, Швеции, Соедин...
Article
Full-text available
The Pan-Eurasian Experiment (PEEX) Science Plan, released in 2015, addressed a need for a holistic system understanding and outlined the most urgent research needs for the rapidly changing Arctic-boreal region. Air quality in China, together with the long-range transport of atmospheric pollutants, was also indicated as one of the most crucial topic...
Article
Full-text available
Many cities in the world experience significant air pollution from residential wood combustion. Such an advection–diffusion problem as applied to geographically distributed small-scale pollution sources presently does not have a satisfactory theoretical or modeling solution. For example, statistical models do not allow for pollution accumulation in...
Article
Full-text available
Urban landscape combines built-up areas with strongly altered natural (green and blue) and other open spaces. Voluminous literature examines urban socio-environmental interactions in tropical and temperate cities, whereas high-latitude cities are rarely considered. Here, we create a historical perspective on urban green (vegetation) and blue (water...
Article
Full-text available
On example of the city of Nadym, located in the Yamalo-Nenets Autonomous Area, the authors consider the socio-ecological problems of the development of green, blue and white open urban spaces. The research approach presented in the article is based on the study of a multifaceted complex of urban social and natural systems in their integrated unity,...
Preprint
Full-text available
The Pan-Eurasian Experiment (PEEX) Science Plan, released in 2015, addressed a need for a holistic system understanding and outlined the most urgent research needs for sustainable development in the Artic-boreal region. Air quality in China and long-range transport of the atmospheric pollutants was also indicated as one of the most crucial topics o...
Article
Full-text available
Persistent warm urban temperature anomalies – urban heat islands (UHIs) – significantly enhance already amplified climate warming in the Arctic. Vulnerability of urban infrastructure in the Arctic cities urges a region-wide study of the UHI intensity and its attribution to UHI drivers. This study presents an overview of the surface and atmospheric...
Article
Full-text available
Sustaining urban environmental quality requires effective policy measures that integrate local monitoring and contextualized high-resolution modelling with actionable scenarios. Knowledgeable decision making in this field can nowadays be supported by an array of atmospheric models, but their transfer into an Integrated Urban hydrometeorological, cl...
Preprint
Full-text available
Many cities in the world experience significant air pollution from residential wood combustion. Such an advection-diffusion problem as applied to geographically distributed small-scale pollution sources presently does not have a satisfactory theoretical or modelling solution. For example, statistical models do not allow for pollution accumulation i...
Article
Full-text available
In this study, we evaluated the climatology and interannual variability of marine cold-air outbreaks (MCAOs) in the Russian Arctic marginal seas (from the Barents to Chukchi seas). We used a simple index for identifying MCAOs based on the vertical potential temperature gradient between the sea surface and the 800 hPa level. We calculated the index...
Presentation
Full-text available
Wind energy has become a mainstream energy resource. However, continued innovation is needed to realize the potential of wind to serve the global demand for clean energy.
Article
Full-text available
The impacts of climate change such as extreme heat waves are exacerbated in cities where most of the world's population live. Quantifying urbanization impacts on ambient air temperatures (Tair) has relevance for human health risk, building energy use efficiency, vector-borne disease control and urban biodiversity. Remote sensing of urban climate ha...
Article
Full-text available
Urban air quality is one of the most prominent environmental concerns for modern city residents and authorities. Accurate monitoring of air quality is difficult due to intrinsic urban landscape heterogeneity and superposition of multiple polluting sources. Existing approaches often do not provide the necessary spatial details and peak concentration...
Article
The urban heat island (UHI) is one of the most evident local climate phenomena in urbanized areas. Although much is known about the UHI in low-and mid-latitude cities, knowledge about the UHI in high latitudes is still fragmentary. Understanding this urban climate phenomenon in the high latitudes is essential to support sustainability and resilienc...
Chapter
Full-text available
The International Panel for Climate Change (IPCC) has recently envisioned a number of detrimental environmental effects and challenges that will emerge with the global warming in excess of the 1.5 o C limit set by the Paris Agreement. The Arctic was mentioned as a particularly vulnerable region on the Earth with rapid and amplified warming affectin...
Article
Although there is a growing body of research on Arctic urbanisation and the development of cities in harsh polar climate, few studies focus on the long-term interaction of urban environments with the natural world and society. As the search for determinative links between natural environmental characteristics and socio-cultural phenomena is exceedi...
Article
Full-text available
Detailed temperature maps are required in various applications. Any temperature interpolation over complex terrain must account for differences in land cover and elevation. Local circulations and other small-scale factors can also perturb the temperature. This study considers the surface air temperature, T, mapping with geo-statistical kriging. The...
Article
Full-text available
We investigate the scaling for decaying turbulence kinetic energy (TKE) in the free-convective boundary layer, from the time the surface heat flux starts decaying, until a few hours after it has vanished. We conduct a set of large-eddy simulation experiments, consider various initial convective situations, and prescribe realistic decays of the surf...
Article
Full-text available
Urban air quality is one of the most prominent environmental concerns for a modern city dweller. Accurate monitoring of air quality is difficult due to intrinsic urban landscape heterogeneity and superposition of multiple polluting sources. Existing approaches often do not provide the necessary spatial details and peak concentrations of pollutants,...
Article
Full-text available
Warm urban climate anomalies are a challenging problem for city’s economy and ecology. This problem is even more pressing in boreal environment with its sensitive ecosystems and considerable anthropogenic urban heat flux. The boreal regions of Eurasia witness both rapid urbanization and accelerated regional warming in the twenty-first century. Stil...
Article
Full-text available
Satellite studies using the normalized difference vegetation index (NDVI) have revealed changes in northern Eurasian vegetation productivity in recent decades, including greening in tundra and browning in the boreal forests. However, apparent NDVI changes and relationships to climate depend on the temporal and spatial sampling and the biome and for...
Article
Full-text available
The Arctic is a cloudy place. It has been recognized that the Arctic cloud cover is sensitive to different climatic factors such as sea ice extent and atmospheric circulation indices. Moreover, several influential climate feedbacks, e.g. the summertime cloud‐radiation feedback, have been recognized. Yet, the cloud cover studies were limited in time...
Presentation
Full-text available
Significant multi-decadal predictability is already known for sea surface temperature anomalies in the North Atlantic and Nordic Seas. Those anomalies have an impact on typical large-scale circulation patterns of the Atlantic- European region. More specifically, it has been suggested that frequency and persistence of the atmospheric blockings in th...
Article
Full-text available
The Arctic has rapidly urbanized in recent decades with 2 million people currently living in more than a hundred cities north of 65∘ N. These cities have a harsh but sensitive climate and warming here is the principle driver of destructive thawing, water leakages, air pollution and other detrimental environmental impacts. This study reports on the...
Article
Full-text available
Systematic errors in forecast near-surface air temperature (SAT) still constitute a considerable problem for numerical weather prediction (NWP) at high latitudes. Numerous studies in the past have attempted to reduce this problem through recalibration of physical parameterization schemes and better approximation of the surface energy budget. The er...
Article
Full-text available
Urban temperature anomalies, frequently referred to as the urban heat islands (UHIs), are of the most distinct and influential climatic factors with significant impact on urban life and environment. However, UHIs in high latitudes are still studied only fragmentary. There is a knowledge gap related to the urban temperature distinction with respect...
Conference Paper
Full-text available
The severe continental climate of the northern high latitudes is characterized by a generally negative surface heat balance and persistent strong static stability of the lower atmosphere. Such conditions favor localized surface temperature anomalies of large amplitude. It has been found that the locations of such anomalies correspond to urban areas...
Article
Full-text available
The Arctic has rapidly urbanized in recent decades with two million people currently living in more than a hundred cities north of 65°N. These cities have a harsh but sensitive climate and warming here is the principle driver of destructive thawing, water leakages, air pollution, and other detrimental environmental impacts. This study reports on th...
Article
Full-text available
This study examines the atmospheric and oceanic heat transports in preindustrial control and historical runs of 15 fully coupled global climate models from the CMIP5 project. The presence of Bjerknes compensation is confirmed in all models by the strong anticorrelation and approximately equal magnitude of the anomalies of these heat transports. Pre...
Article
Full-text available
Dense meteorological networks are needed to advance understanding of urban climatology in the northern polar region where the global warming is rapid and amplified. High quality and density urban temperature datasets are required to monitor thawing processes in urban soils, properly assess and project climatic trends in human comfort, air quality a...
Technical Report
Full-text available
The main objective of the TRAKT-2018 (Transferable Knowledge and Technologies for High-Resolution Environmental Impact Assessment and Management) project is to implement a novel technology for the high-resolution environmental impact assessment. Responsible and sustainable environmental management requires accurate high-resolution environmental inf...
Article
For over a decade, several research groups have been developing air-sea heat flux information over the global ocean, including latent (LHF) and sensible (SHF) heat fluxes over the global ocean. This paper aims to provide new insight into the quality and error characteristics of turbulent heat flux estimates at various spatial and temporal scales (f...
Article
Full-text available
The meridional transport of heat is a critical component of the Earth’s climate system. If the total heat transported by the climate system is approximately constant, then the anomalies of heat transported by the atmosphere and ocean should be approximately equal and opposite, a scenario now called Bjerknes compensation. This has previously been fo...
Article
Full-text available
Anthropogenic heat and modified landscapes raise air and surface temperatures in urbanized areas around the globe. This phenomenon is widely known as an urban heat island (UHI). Previous UHI studies, and specifically those based on remote sensing data, have not included cities north of 60 • N. A few in situ studies have indicated that even relative...
Article
Full-text available
For over a decade, several research groups have been developing air-sea heat flux information over the global ocean, including latent (LHF) and sensible (SHF) heat fluxes over the global ocean. This paper aims to provide new insight into the quality and error characteristics of turbulent heat flux estimates at various spatial and temporal scales (f...
Article
Full-text available
Street-level urban air pollution is a challenging concern for modern urban societies. Pollution dispersion models assume that the concentrations decrease monotonically with raising wind speed. This convenient assumption breaks down when applied to flows with local recirculations such as those found in topographically complex coastal areas. This stu...
Conference Paper
Full-text available
Observations of extreme conditions, characterized by high heat flux, rapidly changing surface wind, or strong ocean current, are rare. Although analyses provide estimates of these conditions, because there are few observations to begin with, it is difficult to calibrate and validate an analysis or a retrieval assuming independent observations (cf....
Article
Full-text available
A long-term climatology of cloudiness over the Norwegian, Barents and Kara Seas (NBK) based on visual surface observations is presented. Annual mean total cloud cover (TCC) over the NBK is almost equal over solid-ice (SI) and open-water (OW) parts of NBK (73±3% and 76±2% respectively). In general, TCC has higher intra- and inter-annual variability...
Article
Full-text available
In this study, we assessed the large-scale circulation anomalies leading to wintertime air pollution episodes in Bergen, Norway. Bergen is an example of a city, where a strong interplay between large-scale and local circulation features is relevant. Certain large-scale circulation regimes that are different from the usually assumed large-scale stag...
Article
Full-text available
Modern human societies have accumulated considerable power to modify their environment and the earth's system climate as the whole. The most significant environmental changes are found in the urbanized areas. This study considers coherent changes in vegetation productivity and land surface temperature (LST) around four northern West Siberian cities...
Article
Full-text available
The northern Eurasian regions and Arctic Ocean will very likely undergo substantial changes during the next decades. The Arctic–boreal natural environments play a crucial role in the global climate via albedo change, carbon sources and sinks as well as atmospheric aerosol production from biogenic volatile organic compounds. Furthermore, it is expec...
Article
Full-text available
Studies of the normalized difference vegetation index (NDVI) have found broad changes in vegetation productivity in high northern latitudes in the past decades, including increases in NDVI ('greening') in tundra regions and decreases ('browning') in forest regions. The causes of these changes are not well understood but have been attributed to a va...
Article
Full-text available
Studies of the normalized difference vegetation index (NDVI) have found broad changes in vegetation productivity in high northern latitudes in the past decades, including increases in NDVI (‘greening’) in tundra regions and decreases (‘browning’) in forest regions. The causes of these changes are not well understood but have been attributed to a va...
Article
Full-text available
We present an analysis of the interaction between a topographically forced recirculation of the large-scale flow above an urbanized coastal valley and a local breeze-like circulation. We found that such an interaction can enhance the stagnation inside the valley under cold air pool conditions. Analysis of a large dataset of air quality measurements...
Conference Paper
Full-text available
Growing capacity and accessibility of high-performance computing open qualitatively new perspectives on personalization of climate services. The personalized climate service is essentially and necessarily a set of technological instruments (models, knowledge databases as well as automated web interfaces to them), which minimize the need for an educ...
Article
Full-text available
Exploration and exploitation of oil and gas reserves of northern West Siberia has promoted rapid industrialization and urban development in the region. This development leaves significant footprints on the sensitive northern environment, which is already stressed by the global warming. This study reports the region-wide changes in the vegetation co...
Conference Paper
Full-text available
A simple energy-balance model suggested that the climatic heat forcing of SAT should reciprocally scale with the depth of the planetary boundary layer. It intro-duces a strong selective and asymmetric response mech-anism in the climate system, which amplifies the SAT trends in the areas dominated by the shallow SBL. This mechanism is the most prono...
Article
Full-text available
Dynamics of atmosphere–ice–ocean interactions in the high latitudes. What: Scientists from 13 countries involved with modeling and observing the coupled high-latitude weather and climate system discussed our current understanding and challenges in polar prediction, extreme events, and coupled processes on scales ranging from cloud and turbulent pro...
Article
Full-text available
The Earth has warmed in the last century and a large component of that warming has been attributed to increased anthropogenic greenhouse gases. There are also numerous processes that introduce strong, regionalized variations to the overall warming trend. However, the ability of a forcing to change the surface air temperature depends on its spatial...
Data
Supplementary Figures 1-2