Abstract Orography significantly influences global climate patterns. Previous studies show the North American mountain range (NAMR) impacts regional climates seasonally but have not thoroughly illustrated the seasonally different atmospheric responses in the lower and upper troposphere, respectively. Using the Community Earth System Model, version 1.2, with a slab ocean configuration, we investigate the NAMR’s seasonal impacts by simulating scenarios with and without the mountain range. Our findings reveal that the NAMR induces contrasting responses in sea surface temperature (SST) and precipitation off California in different seasons, indicating different underlying mechanisms. Through the analysis of large-scale circulation and local energy budgets, we find that in summer, the NAMR reinforces the North Pacific high, causing SST cooling and drying off California. While the coastal cooling is strongest in summer, a broader offshore cooling signal persists across seasons. This signal propagates to the equatorial Pacific via northeasterly, influencing the intertropical convergence zone (ITCZ) and initiating a climatic signal through the Pacific meridional mode, which crosses the equator and affects Southern Hemisphere (SH) temperatures. In winter, the NAMR reduces wind speed and evaporation, leading to SST warming off California, amplified by SST–cloud feedback. In the upper troposphere, we observe seasonal shifts in jet stream patterns: During winter, there is a weakened, equatorward-shifted jet over the Pacific and a strengthened, poleward-shifted branch over the Atlantic; in summer, the jet stream intensifies over and downstream of the mountains while weakening upstream. Our research highlights distinct seasonal mechanisms by which the NAMR influences climate patterns, linking midlatitude climate variations to equatorial, cross-hemispheric and global changes.

Martian meteorites, the only available samples of Martian lithologies, provide unique insights into martian magmatism. Olivines in these meteorites contain complex phosphorus (P) zoning, which shed insights into the behaviour of mafic magmas in the martian crust. These olivines crystallized in multiple stages in ascending magmas, and preserved compositional zoning, particularly in P, due to its low diffusivity. Although previous studies have documented P zoning in martian olivines and attributed its formation to rapid crystallization events in magma storage zones within the crust, the processes responsible for the undercooling and fast olivine growth remain unresolved. This study addresses the challenge of interpreting P zoning in martian olivines to better understand the conditions which affected their crystallization histories. Using high-resolution P X-ray maps and microprobe traverses, we show that P zoning in olivine megacrysts from shergottites (martian basalts) and chassignites (martian dunites) consistently records rapid crystallization events at high undercooling due to magma ascent through the martian crust. These zoning patterns, observed in cores, mantles, and rims of olivines from hypabyssal and intrusive samples, highlight different crystallisation conditions during staging, ascent and emplacement of magmas at varying crustal depths. P zoning in olivine-phyric shergottites, viewed in the light of previous thermobarometry results, record initial olivine nucleation in the lower crust, ascent to the mid-crust and final rapid crystallization in the shallow subsurface. Similarly, we inferred multiple cycles of magma ascent and storage in the martian crust from the P zoning in poikilitic and non-poikilitic regions of a poikilitic shergottite. We also provide evidence from P zoning in olivines to differentiate between magma storage relatively deep in the crust and shallow, hypabyssal emplacement. The nature of P zoning during the final stages of olivine crystallization can serve as in-situ evidence of the eruptive behaviour of shallow magma bodies. Further analyses of available meteorites and olivines from future sample return missions will be fundamental to build a holistic model of martian magma plumbing systems and its evolution through time

Abstract Climate models exhibit an approximately invariant surface warming pattern in typical end-of-century projections. This feature has been used extensively in climate impact assessments for fast calculations of local temperature anomalies, with a linear procedure known as pattern scaling . At the same time, emerging research has also shown that time-varying warming patterns are necessary to explain the time evolution of effective climate sensitivity in coupled models, a mechanism that is known as the pattern effect and that seemingly challenges the pattern scaling understanding. Here, we present a simple theory based on local energy balance arguments to reconcile this apparent contradiction. Specifically, we show that the pattern invariance arises from the combination of exponential forcing, linear feedbacks, a constant forcing pattern, and linear changes in heat transport. These conditions are approximately met in typical Coupled Model Intercomparison Project phase 6 (CMIP6) shared socioeconomic pathways (SSPs), except in the Arctic where nonlinear feedbacks are important and in regions where different aerosol projections alter the forcing pattern. In idealized experiments where concentrations of carbon dioxide (CO 2 ) are abruptly increased, such as those used to study the pattern effect, the warming pattern evolves considerably over time because of spatially inhomogeneous ocean heat uptake, even in the absence of nonlinear feedbacks. Our results illustrate why typical future projections are amenable to pattern scaling and provide a plausible explanation of why more complicated approaches, such as nonlinear emulators, have only shown marginal improvements in accuracy over simple linear calculations. Significance Statement In typical end-of-century climate projections from comprehensive models, the ratio between local and global surface temperature anomalies is approximately time and scenario invariant. This feature has enabled fast calculations of local temperature changes by scaling the global average with a constant pattern. At the same time, idealized quadrupling of CO 2 (4xCO 2 ) experiments show a different behavior and a considerable time evolution of the warming pattern. We present a simple theory based on local energy balance to reconcile this apparent contradiction. Specifically, we show that the pattern invariance arises under a set of conditions that are approximately satisfied typical end-of-century scenarios. Our findings clarify why scaling the global average to calculate local temperature anomalies is effective for most future projections.

Many routine measurements of the solar wind plasma and interplanetary magnetic field (IMF) are made at the L1 Sun–Earth Lagrange point so it is helpful to characterize the errors introduced in propagating these measurements to the near-Earth environme

ABSTRACT We present the detection and validation of a small, temperate transiting exoplanet orbiting TOI-1080 every 3.9652482$_{-0.0000015}^{+0.0000014}$ d. The host is a quiet M4V star at 25.6 pc. The planet signal was first detected by the Transiting Exoplanet Survey Satellite (TESS) and validated using TESS and ground-based observations. By fitting the available light curves, the planet radius is measured to be 1.200 $\pm$ 0.058 R$_{\rm{\oplus }}$ and its equilibrium temperature of $368_{-10.}^{+12}$ K. With Near Infra Red Planet Searcher (NIRPS) radial velocities, we are able to place a 3$\sigma$ upper limit on the mass of TOI-1080 b of 10.7 M$_{\rm{\oplus }}$. Our injection-recovery tests enable us to discard additional transiting planets in the TOI-1080 system with radii down to 0.9 R$_{\rm{\oplus }}$ and periods between 0.5 and 7.7 d, and planets with radii larger than 1.4 R$_{\rm{\oplus }}$ for periods up to 19 d. We demonstrate that it is highly amenable to characterization of its mass and putative atmosphere. In particular, we find that TOI-1080 b is an exceptional target for the ongoing JWST + HST Rocky Worlds DDT programme, having a priority score that is higher than four out of nine targets currently being investigated by the programme. TOI-1080 b can be added to the sample of nearby benchmark planets accessible for detailed study with JWST.