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The diurnal cycle of precipitation and its associated land‐sea breeze circulation over coastal northern Australia are investigated using surface wind speed and enthalpy (latent and sensible heat) fluxes from the Cyclone Global Navigation Satellite System. Composite results during the austral summer of 2018–2022 show that diurnal precipitation propagates westward from the Cape York Peninsula into the Gulf of Carpentaria. The diurnal cycle of precipitation and surface wind speed are strongly coupled, with the wind speed maximum slightly leading the precipitation maximum. Additionally, analysis of the moist static energy budget shows that surface fluxes help support the westward‐propagation of diurnal precipitation. These results—based on novel satellite data and reanalysis—are consistent with previous studies that have examined the impact of the land‐sea breeze on the diurnal cycle of precipitation. The results provide a benchmark for model representation of this important atmosphere‐ocean‐land interaction. Plain Language Summary: The modulation of the diurnal cycle of precipitation over coastal northern Australia by surface winds was studied using the recently launched NASA Cyclone Global Navigation Satellite System (CYGNSS). Results show a strong connection between the daily cycles of precipitation and surface wind speed, with an offshore wind speed maximum leading the precipitation maximum by a few hours. Westward propagation of diurnal precipitation and wind speed signals occurs from the Cape York Peninsula into the Gulf of Carpentaria. A thermodynamic analysis supports the importance of the wind speed signal and associated surface fluxes for fostering offshore precipitation propagation. The novelty of this paper lies in the use of the new CYGNSS retrievals, which provide better space and time coverage of surface wind speed than previous satellite‐based measurements and are not as negatively affected by precipitation contamination. Key Points: Cyclone Global Navigation Satellite System wind speeds and latent heat fluxes are used to study the diurnal cycle over the northern Australia coastal regionEnhanced diurnal precipitation is associated with enhanced surface wind speed and convergenceDiurnal precipitation and surface wind speed signals propagate westward in tandem from the Cape York Peninsula [ABSTRACT FROM AUTHOR]

In 1859 the Dutch historian, L.C.D. van Dijk published a book on the voyages of discovery made by Jan Carstenszoon in 1623 and Jean Etienne Gonzal in 1756 to the Gulf of Carpentaria. The book contains a commentary of the two voyages as well as a copy of Carstenszoon's journal. It also contains a curious map that not only renames the Gulf of Carpentaria and the west coast of Cape York Peninsula, but also questions the naming of Arnhem Land and some of its named locations. This paper examines some of the possible reasoning behind this unusual map. [ABSTRACT FROM AUTHOR]

Observations and analyses of low-level convergence lines over the Gulf of Carpentaria region of northeastern Australia made during the second and third Gulf Lines EXperiments (GLEX II and GLEX III) are reported. During GLEX II, the initiation of the North Australian Cloud Line (NACL) was documented using a small autonomous aircraft and two Doppler sodars. NACLs are long convergence lines that form on the western side of northern Cape York Peninsula and are typically marked by a line of contiguous cumulus or cumulus congestus cloud. The observations show that the degree of asymmetry between west-coast and east-coast sea breezes (as characterized by the wind field) depends on the strength of the background easterlies, and that NACLs develop only when the background easterlies are sufficiently large (≥ 5 m s−1). GLEX III focused on morning glories, which are (mostly) southwestward-moving bore-like convergence lines that originate over the southern part of the gulf region. The field experiment involved Doppler sodar measurements as well as high-temporal-resolution data from operational automatic weather stations. The sodar measurements showed that undular bore-like morning glory cloud lines develop only when the background easterlies are sufficiently weak (≤ 10 m s−1) and that strong bore-like morning glories develop when the background winds exceed about 10 m s−1. If the background easterlies are too strong, no morning glories develop. Numerical simulations show that the structure of convergence line produced depends on the strength of the collision between the sea breezes from each side of the Cape York Peninsula, which in turn depends on the strength of the background easterlies. When the easterlies are weak (≤ 10 m s−1), the sea breezes have similar depths and strengths, and their collision is relatively violent, whereas when the background easterlies are strong (> 10 m s−1) the sea breezes have very different depths and strengths and their collision is comparatively benign. [ABSTRACT FROM AUTHOR]