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Time frame: Begin date 4/21/2019 - End date 8/25/2019. General study design- We subjected nine large-scale, flow-through outdoor stream mesocosms in California’s Sierra Nevada to three flow regime treatments: a flow regime based on historic average conditions (current treatment), a mitigated climate change scenario where low flow begins three weeks earlier than currently (3-week treatment), and an unmitigated climate change scenario where low flow begins six weeks earlier than currently (6-week treatment). Over the course of a season, we regularly measured primary production; community composition, production, and emergence of benthic and emergent stream invertebrates; and Brewer’s Blackbird (Euphagus cyanocephalus) feeding activity. We tested for immediate vs. delayed effects of advanced low flows by combining the period of the study (i.e., start, middle, and end) with the treatment, creating a variable that captures both timing and treatment effects (i.e., period-treatment). We ran a piecewise structural equation model to elucidate and compare mechanisms driving low-flow effects on stream invertebrate production and emergence. Methods description- We used nine channels that are 50 m long by 1 m wide, consist of six pools connected by long riffle sections in a meandering fashion, and are fed by the adjacent Convict Creek. We assigned each channel to one of three treatments (with three replicate channels each) in a block design. The three treatments were: (1) current hydrologic conditions based on the historic (long-term) hydrograph at Convict Creek (based on US Geological Survey gage 10265200), with a flow regime that reaches baseflow conditions around August 3rd (i.e., current treatment); (2) hydrologic conditions under a mitigated climate change scenario, where the stream would return to baseflow conditions three weeks earlier than it currently does (i.e., 3-week treatment); and (3) hydrologic conditions under unmitigated climate change, where the stream would return to baseflow six weeks earlier than it currently does (i.e., 6-week treatment). We regulated discharge by controlling sluice gates at the head of each channel. Flows in the channels differed by one order of magnitude between high-flow and low-flow conditions (i.e., 15 L/s and 1.5 L/s, respectively), following a typical Sierra Nevada stream hydrograph for a small stream. Channels were inspected and maintained daily, were heavily instrumented (see next section), and were monitored and sampled for several responses: primary production, secondary production, benthic and emerging stream invertebrates (composition and abundance), and visitation by riparian birds. The three periods we designated in the study are start (5/11/2019 - 6/10/2019), middle (6/11/2019 - 8/2/2019), and end (8/3/2019 - 8/21/2019). We measured water depth and water temperature every five minutes throughout the experiment (4/21/2019–8/25/2019) with replicated pressure transducers (HOBO U20L-04, Onset). We placed a pressure transducer in the fifth pool downstream in each channel and two emerged sensors on land to correct data for fluctuations in atmospheric pressure, and thus calculate water level (i.e., pool depth). Water level series were subsequently transformed into discharge series via channel-specific rating curves. Rating curves were developed for each channel by estimating discharge manually using channel depth and velocity measurements taken with a Marsh-McBirney Flo-Mate 2000 current meter throughout the summer (17-26 repeated estimates per channel). We measured water temperature using the same HOBO U20L-04 sensors that recorded data every five minutes in pools. We averaged discharge and water temperature to hourly values, which we then used to calculate daily metrics (e.g., daily mean, minimum, maximum, and diel range). We estimated epilithic biofilm primary production using the light/dark bottle method at each channel, once every three weeks. We calculated epilithic biofilm respiration (ER), net primary production (NPP), and the sum of their absolute values–gross primary production (GPP). We used three representative cobbles from the streambed for each sample and measured their surface area using aluminum foil to correct for differences in surface area. All primary production measurements were taken during peak sunlight hours between 10 am and 2 pm using two 90-minute incubation periods for light, followed by dark measurements. Benthic stream invertebrates were removed from rocks prior to incubation. We conducted three replicates for each channel at each sampling date (n = 162). Daily epilithic biofilm GPP per channel was estimated by multiplying the channel average hourly rate by the number of sunlight hours at each date (n = 54). We estimated daily epilithic biofilm ER per channel by multiplying the channel average hourly rate by 24 hours at each date (n = 54). Daily primary production was then estimated for the interval between each sampling date by averaging the bookend interval values. We multiplied the average interval value by the number of days in the interval and finally summed these values to generate cumulative seasonal channel estimates (n = 9). We sampled benthic stream invertebrates using a 500-micron Surber sampler at six visit dates three weeks apart throughout the experiment. Each sample was a composite of three subsamples (two riffles and one pool sample for 0.279 m^2 total) to represent the overall stream community. We took benthic samples for the current and 6-week treatment channels (n = 36) and stored them in 70% ethanol. We then subsampled the composite samples using a rotating-drum splitter in the laboratory to sort and identify at least 500 individuals from each composite sample under a stereomicroscope. All subsamples were completely processed to avoid bias regarding the size of individuals picked and identified. Benthic stream invertebrates were identified to the highest resolution possible, typically genus or species level, and all intact specimens were measured. Benthic stream invertebrate biomass was then estimated using published taxon-specific length-mass relationships. The subsampled community was multiplied by the inverse of the fraction of the total sample that was identified (e.g., if ¼ of the sample was identified to get a count over 500 individuals, then the abundance of each taxon was multiplied by 4). We assigned length values to these extrapolated individuals (and individuals that could be identified but not measured due to damage) using the length values from randomly selected individuals of the same taxon in the sample. We sampled emergent stream invertebrates using emergence traps, each deployed for 72 hours every three weeks during the experiment. We sampled emergence four additional times halfway between the three-week intervals for every sample visit after the second one when flows began to differ between treatments (n = 90 overall). We deployed emergence traps at the tail of riffles (to capture the influence of both riffle and pool habitat) next to HOBO sensors. We identified emergent insects to genus or family level (depending on taxa), and measured the length of intact specimens. Emergence traps were tent-shaped, covered 0.33 m2 of the stream, and had 2 mm white mesh. We noticed Brewer's Blackbirds (Euphagus cyanocephalus) feeding in channels at the onset of low flow in the 6-week treatment channels (June 22, 2019). We recorded the feeding behavior of Brewer’s Blackbirds shortly thereafter by observing the time duration that any bird of this species occupied the benthos of the channels over a 30-minute period periodically throughout the remainder of the experiment. We observed all channels every few days initially but switched to weekly observations once Brewer’s Blackbirds fledged and moved to meadow habitat. Laboratory, field, or other analytical methods- We estimated benthic stream invertebrate secondary production via a combination of three methods. We used the size-frequency method for taxa that were abundant throughout the experiment (i.e., >1% of total abundance) and had known generation times, excluding Chironomidae, Oligochaeta, Turbellaria, and Muscidae. For Chironomids, we used the instantaneous growth rate method. Production was calculated using regression equations for non-Tanypodinae chironomids, which incorporate mean temperature into growth estimates for small, medium, and large chironomids. Finally, we used the production-to-biomass ratio method (P/B) for the remaining taxa, including Tanypodinae, by multiplying seasonal biomass by known P/B ratios in the literature of the closest related taxa possible. Uncertainty in production from P/B ratios is unlikely to affect our results, as taxa in this group comprised <1% of the total assemblage production. We estimated emergent insect biomass using published, taxon-specific length-mass relationships. *Quality control- Data was recorded in hard copies and digitally to reduce the risk of mistyped data. Data was plotted visually for outliers that were erroneous and paper copies were referenced to ensure values were correct. # Climate change is poised to alter mountain stream ecosystem processes via organismal phenological shifts ## Description of the Data and file structure [https://doi.org/10.6078/D10712](https://doi.org/10.6078/D10712) ### Details for: Discharge\_dryad.csv * Dataset description: The dataset includes the average discharge of each channel on each day of the experiment taken with U20 Onset sensors recording every 15 minutes. Sensors were located in pools near the downstream end of channels and secured to cinder blocks at the streambed. Variables * Date: Date with day, month, and year. The format is month/day/year and the year is 2019. * Channel: Channel number beginning at the upstream channel closest to Convict Creek as #1 and ending with the downstream channel farthest from Convict Creek being #9 * Treatment: The treatment of the channel as described above in methods * Discharge_Av_Chan_L_s: Average daily discharge (L/s). Raw water depth data is collected from sensors and transformed using rating curves created for each channel using 22 measuring dates throughout the experiment. Rating curves are not perfect estimates, however. Discharge values estimated above 30 L/s by the rating curve were set to 30 L/s because flows were unlikely to be any higher based on manual discharge estimates and channel capacity. Discharge estimated below 0 L/s were set to 0 L/s, although no channels actually dried. ### Details for: Water\_Temperature\_dryad.csv * Dataset description: The dataset includes daily mean, minimum, and maximum water temperatures of each channel taken with U20 Onset sensors recording every 15 minutes. Variables * day: Date with day, month, and year. Format is month/day/year where the year is 2019. * Channel: Channel number beginning at the upstream channel closest to Convict Creek as #1 and ending with the downstream channel farthest from Convict Creek being #9 * Treatment: The treatment of the channel as described above in methods * Temp_Av_Daily_C: Mean daily temperature of a channel in degrees Celsius. * Temp_Max_Daily_C: Maximum daily temperature of a channel in degrees Celsius. * Temp_Min_Daily_C: Minimum daily temperature of a channel in degrees Celsius. ### Details for: Benthic\_Macroinvertebrates\_dryad.csv * Dataset description: The dataset includes the lowest taxonomic identification and size of all benthic macroinvertebrates in the study. Variables * Date: Date with day, month, and year. Format is month/day/year where the year is 2019. * Channel: Channel number beginning at the upstream channel closest to Convict Creek as #1 and ending with the downstream channel farthest from Convict Creek being #9 * Treatment: The treatment of the channel as described above in methods * Order: The order of the organism * Family: The family of the organism * Lowest: The lowest taxonomic identification possible for the organism, typically genus. * Corrected_Size_mm: The length of the organism measured from its head to the end of its abdomen in most cases. Organisms without a head such as Pisidium or snails had the widest cross-section measured as their length. ### Details for: Primary\_production\_dryad.csv * Dataset description: The dataset includes primary production data taken using the light dark bottle method. Primary production values are corrected by the surface area of cobbles used. A YSI dissolved oxygen meter was used for measurements. Variables * Date: Date with day, month, and year. Format is month/day/year where the year is 2019. * Channel: Channel number beginning at the upstream channel closest to Convict Creek as #1 and ending with the downstream channel farthest from Convict Creek being #9 * Treatment: The treatment of the channel as described above in methods * Section: The riffle that the substrate originated from. Each channel had three sections measured at each measuring date. Sections are numbered from one-seven with one being the riffle section farthest upstream. * GPP_C_mg_m2: Gross primary production (GPP) measured in mg carbon per m^2. * NPP_C_mg_m2: Net primary production (NPP) measured in mg carbon per m^2. * ER_C_mg_m2: Ecosystem respiration (ER) measured in mg carbon per m^2. * Light hours: the hours of sunlight for the date. This is used to calculate daily values of GPP, NPP, and ER. * GPP_ER_Ratio: The ratio between GPP and ER which indicates if carbon sequestration occurs from primary production. ### Details for: Emergent\_macroinvertebrates\_dryad.csv * Dataset description: The dataset includes the lowest taxonomic identification and size of all emergent macroinvertebrates in the study. Variables * Date: Date with day, month, and year. Format is month/day/year where the year is 2019. * Channel: Channel number beginning at the upstream channel closest to Convict Creek as #1 and ending with the downstream channel farthest from Convict Creek being #9 * Treatment: The treatment of the channel as described above in methods * Order: The order of the organism * Family: The family of the organism * Subfamily: The subfamily of the organism * lowest: The lowest taxonomic identification possible for the organism, typically family, tribe, or genus. * Size_mm: The length of the organism measured from its head to the end of its abdomen. * Sex: The sex of the organism, when detectible. M = male, F = female ### Details for: BrewersBlackbird\_dryad.csv * Date: Date with day, month, and year. Format is month/day/year where the year is 2019. * Time: The time when the 30 minute observation period began. PM and AM are listed with hour and minute. * Channel: Channel number beginning at the upstream channel closest to Convict Creek as #1 and ending with the downstream channel farthest from Convict Creek being #9 * Riparian_time_s: The time in seconds that a bird was observed along the side of a channel. * Benthic_time_s: The time in seconds that a bird was observed within a channel in the channel bed. * Number_individuals: The total number of individual birds observed during the period. * Treatment: The treatment of the channel as described above in methods ## Code/Software Leathers_2024_PNAS_Code.R contains the code used to process, analyze, and plot data. Questions about the code can be addressed to Kyle Leathers - [kyle_leathers@berkeley.edu](mailto:kyle_leathers@berkeley.edu) ## Sharing/access Information Suggested Citation: Leathers, K., Herbst, D., de Mendoza, G., Doerschlag, G., Ruhi, A. (2024), Data for: Climate change is poised to alter mountain stream ecosystem processes via organismal phenological shifts, Dryad, Dataset, [https://doi.org/10.6078/D10712](https://doi.org/10.6078/D10712) Climate change is affecting the phenology of organisms and ecosystem processes across a wide range of environments. However, the mechanisms linking organismal to ecosystem process change in complex communities are uncertain. Here we examined how earlier snowmelt will alter the phenology of stream organisms and ecosystem processes, via a large-scale field experiment in outdoor stream channels. Extended low flows increased water temperature, reducing production-to-respiration ratios by 32%. The stream invertebrate community shifted due to phenological shifts in two-thirds of the taxa, and emergent flux pulses of the dominant insect group (Chironomidae) almost doubled, benefitting a generalist riparian predator. Our study shows that climate change in mountain streams is poised to alter the dynamics of stream food webs via fine-scale changes in phenology—leading to novel predator-prey ‘matches’ or 'mismatches’ even when community structure and ecosystem processes appear stable at the annual scale.

Obesity produces a chronic inflammatory state involving the NFκB pathway, resulting in persistent elevation of the noncanonical IκB kinases IKKε and TBK1. In this study, we report that these kinases attenuate β-adrenergic signaling in white adipose tissue. Treatment of 3T3-L1 adipocytes with specific inhibitors of these kinases restored β-adrenergic signaling and lipolysis attenuated by TNFα and Poly (I:C). Conversely, overexpression of the kinases reduced induction of Ucp1, lipolysis, cAMP levels, and phosphorylation of hormone sensitive lipase in response to isoproterenol or forskolin. Noncanonical IKKs reduce catecholamine sensitivity by phosphorylating and activating the major adipocyte phosphodiesterase PDE3B. In vivo inhibition of these kinases by treatment of obese mice with the drug amlexanox reversed obesity-induced catecholamine resistance, and restored PKA signaling in response to injection of a β-3 adrenergic agonist. These studies suggest that by reducing production of cAMP in adipocytes, IKKε and TBK1 may contribute to the repression of energy expenditure during obesity.

A wavelet variability model (WVM) for simulating solar photovoltaic (PV) power plant output given a single irradiance point sensor timeseries using spatio-temporal correlations is presented. The variability reduction (VR) that occurs in upscaling from the single point sensor to the entire PV plant at each timescale is simulated, then combined with the wavelet transform of the point sensor timeseries to produce a simulated power plant output. The WVM is validated against measurements at a 2-MW residential rooftop distributed PV power plant in Ota City, Japan and at a 48-MW utility-scale power plant in Copper Mountain, NV. The WVM simulation matches the actual power output well for all variability timescales, and the WVM compares well against other simulation methods.

We argue that a primary focus on energy efficiency may not be sufficient to slow (and ultimately reverse) the growth in total energy consumption and carbon emissions. Instead, policy makers need to return to an earlier emphasis on "conservation," with energy efficiency seen as a means rather than an end in itself. We briefly review the concept of "intensive" versus "extensive" variables (i.e., energy efficiency versus energy consumption), and why attention to both consumption and efficiency is essential for effective policy in a carbon- and oil-constrained world with increasingly brittle energy markets. To start, energy indicators and policy evaluation metrics need to reflect energy consumption as well as efficiency. We introduce the concept of "progressive efficiency," with the expected or required level of efficiency varying as a function of house size, appliance capacity, or more generally, the scale of energy services. We propose introducing progressive efficiency criteria first in consumer information programs (including appliance labeling categories) and then in voluntary rating and recognition programs such as ENERGY STAR. As acceptance grows, the concept could be extended to utility rebates, tax incentives, and ultimately to mandatory codes and standards. For these and other programs, incorporating criteria for consumption as well as efficiency offers a path for energy experts, policy-makers, and the public to begin building consensus on energy policies that recognize the limits of resources and global carrying-capacity. Ultimately, it is both necessary and, we believe, possible to manage energy consumption, not just efficiency in order to achieve a sustainable energy balance. Along the way, we may find it possible to shift expectations away from perpetual growth and toward satisfaction with sufficiency.

The present study tested the assumption that deep rectal temperature reflects brain temperature in ethanol-intoxicated mice exposed to a range of ambient temperatures. Adult C57BL/6J mice were injected IP with one of three hypnotic doses of ethanol (3.2, 3.6, or 4.0 g/kg, 20% w/v) or with normal saline and were exposed to ambient temperatures of 15, 22, 32, or 34 degrees C. Thirty minutes post-injection, the mice were killed by cervical dislocation, decapitated and their rectal and brain temperatures were recorded simultaneously. Rectal and brain temperatures in the intoxicated mice increased significantly as the ambient temperature increased and were highly correlated and linearly related with each other. Although correlated, brain and rectal temperatures in these mice did not change in parallel, with brain temperatures increasing less rapidly than rectal temperatures. Additional studies indicated that similar relationships (correlated, but non-parallel) exist between the brain and rectal temperatures at 60, 120, and 180 min after injection of 3.6 g/kg ethanol. These findings suggest that rectal temperature can be used to quantify brain temperature in intoxicated mice, and extend to intoxicated animals evidence that brain temperature is controlled independently from rectal temperature.

Although the relationship between drought - a dimension of climate change - and migration has been explored in a number of settings, prior research has largely focused on out-migration and has not considered climate factors at the migrant destination. However, drought may impact not only out-migration, but also return migration, particularly in settings where temporary labor migration and agricultural reliance are common. Thus, considering drought conditions at origin and destinations is necessary to specify the effects of climate on migrant-sending populations. Using detailed data from the Chitwan Valley Family Study, a household panel study in a migrant-sending area in Nepal, we analyze the effect of drought at the neighborhood level on individual-level out-migration and drought at the origin district on return migration among adults from 2011 to 2017, assessing these associations among males and females separately. In mixed-effect discrete-time regressions, we find that neighborhood drought is positively associated with out-migration and return migration, both internally and internationally among males. Among females, drought is positively associated with internal out-migration and return migration, but not international migrations. We did not find an association between drought at the origin and return migration independent of drought status at the destination. Taken together, these findings contribute to our understanding of the complexity of the impacts of precipitation anomalies on population movement over time.

Abstract Since 1992, the United Nations Framework Convention on Climate Change (UNFCCC), the global governing apparatus of climate planning, has privileged the sovereignty of territorial states. Contemporary political geographical scholarship has since called into question the coherency of the state as a unitary entity and as the sole legitimate arbiter of international politics. This article extends these contributions to planetary climate change adaptation. Through discourse analysis and the multi-scalar institutional and political history of climate planning, this article examines how normative discursive parameters enact prevailing political dynamics that script material futures. Drawing on recent climate planning reports of Palestine and Israel, this article investigates how state discourses operate within an asymmetric geopolitical context where issues of territoriality, sovereignty, and statecraft remain fractured and contested. Climate planning in Israel/Palestine exposes two key institutional constraints of climate governance. First, technical-managerial principles prescribe ahistorical adaptation measures that inadequately address inherently political constraints. Second, the elision of political-economic and historical-cultural contingencies in favor of a universalizing geophysical representation of climate change elides the systemic production of differentiated vulnerability. Consequential of an anachronistic politics of recognition within the UNFCCC, the conditions of climate governance may ultimately embolden the asymmetric status quo. I conclude by highlighting the spatial manifestations (both material and symbolic) of Israeli sovereign violence and the chronic indeterminacy of Palestinian territoriality produced by discursive climate futures.

Intracellular elemental quotas under low and high temperatures for E. huxleyi in constant and fluctuating thermal environments. This dataset includes the growth rates under low and high temperatures for E. huxleyi in constant and fluctuating thermal environments. Global warming will be combined with predicted increases in thermal variability in the future surface ocean, but how temperature dynamics will affect phytoplankton biology and biogeochemistry is largely unknown. Here, we examine the responses of the globally important marine coccolithophore Emiliania huxleyi to thermal variations at two frequencies (1 d and 2 d) at low (18.5 °C) and high (25.5 °C) mean temperatures. Elevated temperature and thermal variation decreased growth, calcification and physiological rates, both individually and interactively. The 1 d thermal variation frequencies were less inhibitory than 2 d variations under high temperatures, indicating that high-frequency thermal fluctuations may reduce heat-induced mortality and mitigate some impacts of extreme high-temperature events. Cellular elemental composition and calcification was significantly affected by both thermal variation treatments relative to each other and to the constant temperature controls. The negative effects of thermal variation on E. huxleyi growth rate and physiology are especially pronounced at high temperatures. These responses of the key marine calcifier E. huxleyi to warmer, more variable temperature regimes have potentially large implications for ocean productivity and marine biogeochemical cycles under a future changing climate.