Despite their impacts on ecosystems, climate, and human health, atmospheric emissions of mineral dust from deserts have been scarcely studied. This work estimated dust emission flux (E) between 1979 and 2014 from two desert regions in the Baja California Peninsula (BCP) using a modified dust parameterization scheme. Subsequently, we evaluated the processes controlling the variability of E at intra- and interannual scales. During the period 1979–2014 peak E were generally recorded in summer (San Felipe) and spring (Vizcaino), and the lowest emissions occurred in autumn (San Felipe) and winter (Vizcaíno). Intra- and interannual variability in E was associated with fluctuations in wind speed and direction, precipitation, and soil moisture, which, in turn, were controlled by the seasonal displacement of the North Pacific high-pressure center. Key drivers of the interannual variability of E are strong El Niño Southern Oscillation (ENSO) events. These climatic events and the hydrometeorological variables mentioned above played a major role in the onset and occurrence of dust events, with the highest annual emissions at Vizcaíno. Besides, a lag of 19 months (San Felipe) and 21 months (Vizcaino) was recorded between the occurrence of relevant E and ENSO events, apparently in response to the effect of this climatic event on precipitation. The climate variability of E in both desert regions was evidenced by the positive trends associated with increases in wind speed and air temperature, and with decreases in precipitation and soil moisture. Finally, our findings suggest that the BCP should be considered as a significant source of dust for the regional inventory of particulate matter emissions from the Earth’s surface.

The influence of El Niño–Southern Oscillation (ENSO) on productivity at upwelling systems has been extensively studied. However, in recent decades, ENSO diversity has been documented; there are more frequent events with anomalies in the central Pacific (CP) causing ecological impacts that are different from the canonical events centered in the eastern Pacific (EP). We hypothesize that ENSO effects on upwelling intensity and its biological response are highly dependent on ENSO diversity. Wavelet coherence was computed for monthly standardized anomalies of Ekman transport and sea surface Chlorophyll-a (Chl-a) concentration from eight upwelling centers located along the west coast of the Baja California peninsula (1993–2022). Ekman transport (ET) showed a non-linear association with ENSO at interannual periodicities between 1.2 and 7 years, as well as semiannual scale variability. Coherence between ENSO and ET showed a reduction in upwelling intensity during CP ENSO events and an increased upwelling intensity after EP El Niño events with regional differences. Our results reveal an influence of northern Pacific circulation that subsequently influences ENSO events during its development and its peak. We detected an influence of SST and wind anomalies on the ENSO–Ekman transport connection associated with the northern Pacific Meridional Mode pattern. The CP shows an important role in sea surface Chl-a concentration anomalies (1998–2022). We highlight the conceptual relevance of distinguishing ENSO diversity, with influential ecological effects associated with CP ENSO events.

Heavy metal pollution in aquatic ecosystems is a critical environmental issue worldwide. In these ecosystems, the seston adsorbs heavy metals from the water and introduces them into the food web, causing potential environmental and health risks. This study analyses how heavy metals (Cd, Hg, Cr, Cu, Pb, Fe, and Mn) are distributed in the water and seston of the Tampamachoco Lagoon, an ecosystem affected by pollution from a thermoelectric plant and by hydrometeorological variability, both of which influence their concentrations. The relationships among metal distribution, physicochemical variables, and the influence of plant emissions in three seasons (rainy, northerly windstorms, and dry) were analyzed. The metal concentrations in seston (Fe > Mn > Pb > Cu > Cr > Hg) were up to four times higher than in the water column (Fe > Mn > Cr > Cd > Pb > Cu > Hg), emphasizing the key role of particulate matter in metal transport and bioavailability. Particularly, the Cd concentrations exceeded WHO thresholds by 527.6% in the water column during the rainy season, while Hg and Pb exceeded the thresholds of the Mexican criteria for the protection of marine aquatic life by 4.05% and 41.6%, respectively. Principal Component Analyses revealed distinct spatiotemporal distribution patterns for metals in water and seston, reflecting the combined effects of natural variability and anthropogenic inputs. The strong association between metals and seston indicates continued contamination and potential risks to aquatic ecosystems. These findings highlight the environmental impact of metals on seston and the need for monitoring to assess aquatic ecosystems’ health. Our results highlight the importance of understanding how metals are distributed between seston and water, and how climate variability affects pollutant redistribution patterns. We propose that water quality regulations need to be rethought and redirected towards the achievement of new strategic objectives that truly integrate the different pollutant sources whose final destination is water bodies, so as to protect and conserve biodiversity and aquatic ecosystems.

Through atmospheric transport, coming from the mainland, an important amount of dust arrives to surface waters of open-ocean regions and many coastal zones. Semi-arid and desert areas tend to act as important sources of dust. The Gulf of California (GC) is one of the most productive marginal seas of the world, and it is surrounded by the semi-arid deserts located in Baja California Peninsula, United States, and Sonora (Mexico). Dust fluxes coming from the BCP during the summer are relevant due to biological impact on the California Gulf. In the northern region of the BCP, meteorological events have not been well studied. These events are known in popular slang as "El Torito". The characterization of a dust event that originated in the Baja California Peninsula (BCP) on June 14, 2016, is presented. Meteorological variables (from North American Regional Reanalysis -NARR), daily sea surface temperature, and aerosol optical thickness (from MODIS) are used to explain the dust event genesis, are used. Results suggest that sea surface temperature fluctuations in the Pacific Ocean off the coast of the BCP generate changes in hydrometeorological variables (wind, relative humidity, and atmospheric pressure) that can give rise to dust events. The June 14 dust storm originates in the San Felipe desert and disperses aeolian to the northern Gulf of California, as shown by aerosol optical thickness images and trajectories simulated with the HYSPLIT model, which establishes vertical distributions with predominant heights between 0 and 500 m.