Galaxy source counts in the infrared provide strong constraints on the evolution of the bolometric energy output from distant galaxy populations. We present the results from deep 24 m imaging from Spitzer surveys, which include %5 ; 10 4 sources to an 80% completeness of '60 Jy. The 24 m counts rapidly rise at near-Euclidean rates down to 5 mJy, increase with a super-Euclidean rate between 0.4 and 4 mJy, and converge below $0.3 mJy. The 24 m counts exceed expectations from nonevolving models by a factor of k10 at S $ 0:1 mJy. The peak in the differential number counts corresponds to a population of faint sources that is not expected from predictions based on 15 m counts from the Infrared Space Observatory. We argue that this implies the existence of a previously undetected population of infrared-luminous galaxies at z $ 1 3. Integrating the counts to 60 Jy, we derive a lower limit on the 24 m background intensity of 1:9 AE 0:6 nW m À2 sr À1 of which the majority ($60%) stems from sources fainter than 0.4 mJy. Extrapolating to fainter flux densities, sources below 60 Jy contribute 0:8 þ0:9 À0:4 nW m À2 sr À1 to the background, which provides an estimate of the total 24 m background of 2:7 þ1:1 À0:7 nW m À2 sr À1 .

We present MIPS observations of the cluster A3266. About 100 spectroscopic cluster members have been detected at 24 µm. The IR luminosity function (LF) in A3266 is very similar to that in the Coma cluster down to the detection limit L IR ∼ 10 43 ergs s −1 , suggesting a universal form of the bright end IR LF for local rich clusters with M ∼ 10 15 M ⊙ . The shape of the bright end of the A3266-Coma composite IR LF is not significantly different from that of nearby field galaxies, but the fraction of IR-bright galaxies (SFR > 0.2M ⊙ yr −1 ) in both clusters increases with cluster-centric radius. The decrease of the blue galaxy fraction toward the high density cores only accounts for part of the trend; the fraction of red galaxies with moderate SFRs (0.2 M ⊙ yr −1 < SFR < 1 M ⊙ yr −1 ) also decreases with increasing galaxy density. These results suggest that for the IR bright galaxies, nearby rich clusters are distinguished from the field by a lower star-forming galaxy fraction, but not by a change in L * IR . The composite IR LF of Coma and A3266 shows strong evolution when compared with the composite IR LF of two z ∼ 0.8 clusters, MS 1054 and RX J0152, with L *. This L * IR evolution is indistinguishable from that in the field, and the Φ * IR evolution is stronger, but still consistent with that in the field. The similarity of the evolution of bright-end IR LF in very different cluster and field environments suggests either this evolution is driven by the mechanism that works in both environments, or clusters continually replenish their star-forming galaxies from the field, yielding an evolution in the IR LF that is similar to the field. The mass-normalized integrated star formation rates (SFRs) of clusters within 0.5R 200 also evolve strongly with redshift, as (1 + z) 5.3 .

We study the infrared (IR) properties of galaxies in the cluster MS 1054-03 at z = 0.83 by combining MIPS 24 µm data with spectra of more than 400 galaxies and a very deep K-band selected catalog. 19 IR cluster members are selected spectroscopically, and an additional 15 are selected by their photometric redshifts. We derive the IR luminosity function of the cluster and find strong evolution compared to the similar-mass Coma cluster. The best fitting Schechter function gives L * IR = 11.49 +0.30 −0.29 L ⊙ with a fixed faint end slope, about one order of magnitude larger than that in Coma. The rate of evolution of the IR luminosity from Coma to MS 1054-03 is consistent with that found in field galaxies, and it suggests that some internal mechanism, e.g., the consumption of the gas fuel, is responsible for the general decline of the cosmic star formation rate (SFR) in different environments. The mass-normalized integrated SFR within 0.5R 200 in MS 1054-03 also shows evolution compared with other rich clusters at lower redshifts, but the trend is less conclusive if the mass selection effect is considered. A nonnegligible fraction (13 ± 3%) of cluster members, are forming stars actively and the overdensity of IR galaxies is about 20 compared to the field. It is unlikely that clusters only passively accrete star forming galaxies from the surrounding fields and have their star formation quenched quickly afterward; instead, many cluster galaxies still have large amounts of gas, and their star formation may be enhanced by the interaction with the cluster.

This paper describes the access to, and the content, characteristics, and potential applications of the tropical cyclone (TC) database that is maintained and actively developed by the China Meteorological Administration, with the aim of facilitating its use in scientific research and operational services. This database records data relating to all TCs that have passed through the western North Pacific (WNP) and South China Sea (SCS) since 1949. TC data collection has expanded over recent decades via continuous TC monitoring using remote sensing and specialized field detection techniques, allowing collation of a multi-source TC database for the WNP and SCS that covers a long period, with wide coverage and many observational elements. This database now comprises a wide variety of information related to TCs, such as historical or real-time locations (i.e., best track and landfall), intensity, dynamic and thermal structures, wind strengths, precipitation amounts, and frequency. This database will support ongoing research into the processes and patterns associated with TC climatic activity and TC forecasting.

Using mid-IR and optical data, we deduce the total infrared (IR) luminosities of galaxies in the Coma cluster and present their infrared luminosity function (LF). The shape of the overall Coma IR LF does not show significant differences from the IR LFs of the general field, which indicates the general independence of global galaxy star formation on environment up to densities $\sim$ 40 times greater than in the field (we cannot test such independence above $L_{ir} \approx 10^{44} {\rm ergs s}^{-1}$). However, a shallower faint end slope and a smaller $L_{ir}^{*}$ are found in the core region (where the densities are still higher) compared to the outskirt region of the cluster, and most of the brightest IR galaxies are found outside of the core region. The IR LF in the NGC 4839 group region does not show any unique characteristics. By integrating the IR LF, we find a total star formation rate in the cluster of about 97.0 $M_{\sun}{\rm yr}^{-1}$. We also studied the contributions of early- and late-type galaxies to the IR LF. The late-type galaxies dominate the bright end of the LF, and the early-type galaxies, although only making up a small portion ($\approx$ 15%) of the total IR emission of the cluster, contribute greatly to the number counts of the LF at $L_{ir} < 10^{43} {\rm ergs s}^{-1}$.Comment: 33 pages, 8 figures, 1 table. Accepted for publication in The Astrophysical Journa