Climate modulates the incidence of mosquito-borne diseases, in part due to climatic impacts on the suitability of vector breeding habitats. While the existence of a mechanistic link between climate and habitat suitability is clear—the aquatic early life stages of mosquitoes are impacted by climate-driven variability in water level and temperature—what is less well-defined is the sensitivity of these habitats to climate variability, which can be dependent on myriad factors such as the physical properties of the habitats as well as the timescale of interest.In this work we focus on the habitats of Aedes aegypti and Aedes albopictus, the urban-adapted vectors of dengue that primarily breed in artificial containers (e.g., water tanks, flower pots, discarded tires). We investigate the climate sensitivity of these habitats using the energy balance container model WHATCH’EM (NCAR). WHATCH’EM simulates the (hourly) temporal evolution of water height and temperature within a container habitat based on user-specified parameters (e.g., container dimensions, shading, thermal conductivity) and climate inputs (e.g., timeseries of air temperature, relative humidity, rainfall). Here we discuss our implementation of this model, using WHATCH’EM to (a) understand model sensitivity within a parameter space informed by existing entomological surveillance data for Sri Lanka, and (b) test habitat sensitivity to climate variability due to the Madden–Julian Oscillation (MJO), the quasiperiodic atmospheric disturbance that primarily drives subseasonal variability in the tropics. By doing so we will assess the extent to which the habitats of dengue vectors show MJO-associated subseasonal climate sensitivities.

The lunar surface evolves over time due to space weathering, and the visible–near-infrared spectra of more mature (i.e., heavily weathered) soils are lower in reflectance and steeper in spectral slope (i.e., darker and redder) than their immature counterparts. These spectral changes have traditionally been attributed to the space-weathered rims of soil grains (and particularly nanophase iron therein). However, understudied thus far is the spectral role of agglutinates—the agglomerates of mineral and lithic fragments, nanophase iron, and glass that are formed by micrometeoroid impacts and are ubiquitous in mature lunar soils. We separated agglutinates and non-agglutinates from six lunar soils of varying maturity and composition, primarily from the 125–250 μm size fraction, and measured their visible–near-infrared reflectance spectra. For each soil, agglutinate spectra are darker, are redder, and have weaker absorption bands than the corresponding non-agglutinate and unsorted soil spectra. Moreover, greater soil maturity corresponds to darker agglutinate spectra with weaker absorption bands. These findings suggest that agglutinates (rather than solely the space-weathered rims) play an important role in both the darkening and reddening of mature soils—at least for the size fractions examined here. Comparisons with analog soils suggest that high nanophase iron abundance in agglutinates is likely responsible for their low reflectance and spectrally red slope. Additional studies of agglutinates are needed, both to more comprehensively characterize their spectral properties (across size fractions and in mixing with non-agglutinates) and to assess the relative roles of agglutinates and rims in weathering-associated spectral changes.

A planetary surface’s thermal infrared (TIR) emissions provide insight into the surface’s composition. Different minerals can be identified by their characteristic TIR spectral signatures. Therefore one can retrieve surface mineral composition by comparing TIR observations of a planetary surface against a library of known mineral TIR spectra measured on Earth. However for airless bodies such as the Moon, creating such a spectral library poses a challenge: minerals exhibit different TIR characteristics when measured in typical terrestrial conditions versus in lunar surface-like environments. We work to overcome this challenge by measuring TIR emission spectra of mineral samples in a chamber that simulates the lunar environment. The Simulated Airless Body Emission Laboratory (SABEL) chamber heats particulate samples under vacuum to generate a thermal gradient akin to that found in the upper regolith (i.e. epiregolith) of airless bodies. The presence of this thermal gradient—modeled to be as steep as ~60K/100 μm for the Moon—is due to airless bodies lacking the convective heat transfer provided by an atmosphere. This thermal gradient is responsible for the altered TIR spectral emission characteristics of the lunar surface, so simulating it in SABEL allows us to measure TIR spectra that are directly comparable to remotely sensed TIR observations from the Diviner Lunar Radiometer (Diviner) instrument aboard the Lunar Reconnaissance Orbiter (LRO). The work presented here focuses on one particular application of SABEL: characterizing the TIR emission spectra of silicate mineral mixtures with the endmembers plagioclase, pyroxene, and olivine. These endmembers bound the typical mineral compositions of the lunar surface. By understanding the TIR characteristics of these endmembers’ mixtures, and in particular how the wavelength position of the Christiansen feature—an emissivity maximum sensed by Diviner—changes for different mixtures, we can better interpret TIR data and their implications for surface composition.