NAEA News, Volume 63, Number 1, February–March 2021

The 210Pb‐7Be‐O3 relationships observed in three aircraft missions over the western Pacific (PEM‐West A and B, TRACE‐P) are simulated with a global three‐dimensional chemical tracer model (GEOS‐CHEM) driven by assimilated meteorological observations. Results are interpreted in terms of the constraints that they offer on sources of tropospheric ozone (O3). Aircraft observations of fresh Asian outflow show strong 210Pb‐O3 correlations in September–October, but such correlations are only seen at low latitudes in February–March. Observations further downwind over the Pacific show stronger 210Pb‐O3 correlations in February–March than in September–October. The model reproduces these results and attributes the seasonal contrast to strong O3 production and vertical mixing over east Asia in September–October, seasonal shift of convection from China in September–October to Southeast Asia in February–March, and slow but sustained net O3 production in Asian outflow over the western Pacific in February–March. Seasonal biomass burning over Southeast Asia in February–March is responsible for the positive 210Pb‐O3 correlations observed at low latitudes. The model reproduces the observed absence of 7Be‐O3 correlations over the western Pacific during September–October, implying strong convective and weak stratospheric influence on O3. Comparison of observed and simulated 7Be‐O3 correlations indicates that the stratosphere contributes less than 20–30% of O3 in the middle troposphere at northern midlatitudes even during spring.

Purpose: To test the hypothesis that the month at which participants complete their first heat exposure will impact the magnitude of adaptations following a 5-day heat acclimation (HA) intervention. Methods: Physically active individuals (n=42) first completed the Israeli Defense Force heat tolerance test (HTT1; 5.0 km·h -1 , 2% grade, 120min, 40°C, 40% relative humidity) and then a modified heat tolerance test (HTT2; 65% vVO 2 max, 2% grade treadmill run, 40°C, 40% relative humidity, until rectal temperature reached 39.5°C) before (pre-HA) and after (post-HA) a 5-day HA protocol. Absolute changes (Δ) for variables associated with the HA response across both HTTs were calculated between post-HA and pre-HA. HTT1 variables include pre-exercise (T0) heart rate (HR), peak HR, average HR, baseline rectal temperature (Trec), T0 Trec, peak Trec, average Trec, Trec rate of rise (RoR), peak mean skin temperature, whole body sweat loss (WBSL), post-exercise rating of perceived exertion (RPE), post-exercise thermal sensation (TS), and post-exercise overall fatigue (FAT). HTT2 variables include total exercise time, T0 HR, peak HR, average HR, baseline Trec, T0 Trec, TrecRoR, peak mean skin temperature, WBSL, RPE, TS, and FAT. All participants completed the study between November and March and were grouped into three groups based on the month of their first heat exposure: November/December (ND), January (J), and February/March (FM) (n=13, 14, & 15, respectively). Comparisons between groups for participant characteristics and Δ of the variables were conducted using one-way ANOVAs and post hoc Tukey HSD (data are mean±SD; significance p≤0.05). Results: There were no significant differences between groups for age, height, weight, VO 2 max, lean mass or fat mass percentage (p>0.05). Compared to ND and J, FM had greater reductions in Δpeak Trec(FM: -0.57±0.33°C, ND: -0.16±0.37°C, J: -0.18±0.37°C, p<0.05) and ΔTrec RoR (FM: -0.004±0.003°C·min -1 , ND: 0.000±0.003°C·min -1 , J: -0.001±0.001°C·min -1 , p<0.05) during HTT1 as well as significant reductions in Δaverage HR (FM: -19±10BPM, ND: -10±9BPM, p<0.05) and an increase in ΔWBSL (FM: 0.13±0.39L, ND: -0.33±0.42L, p<0.05) compared to ND. During HTT2, only ΔWBSL was significantly different between FM and J (FM: 0.37±0.33L, J: 0.17±0.23L, p<0.05). Conclusion: Although all participants were living in the New England region and began testing in the late fall through the winter months (i.e., November to March), greater magnitudes were identified in participants who were tested later into fall/winter than participants who were tested earlier. The statistically and clinically distinct differences highlight the importance of how the time of year can influence adaptations associated with heat acclimation and thermoregulatory research. Funding: DoD BA200299 This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.

Decadal trends are compared in various fields between Northern Hemisphere early winter, November–December (ND), and late-winter, February–March (FM), months using reanalysis data. It is found that in the extratropics and polar region the decadal trends display nearly opposite tendencies between ND and FM during the period from 1979 to 2003. Dynamical trends in late winter (FM) reveal that the polar vortex has become stronger and much colder and wave fluxes from the troposphere to the stratosphere are weaker, consistent with the positive trend of the Arctic Oscillation (AO) as found in earlier studies, while trends in ND appear to resemble a trend toward the low-index polarity of the AO. In the Tropics, the Hadley circulation shows significant intensification in both ND and FM, with stronger intensification in FM. Unlike the Hadley cell, the Ferrel cell shows opposite trends between ND and FM, with weakening in ND and strengthening in FM. Comparison of the observational results with general circulation model simulations is also discussed.

Top working method and bloom density of pollinizers as productive determinant for spur type apple ( Malus x domestica Borkh.) cultivars

Interpretation of the variability of levels of regional background aerosols in the Western Mediterranean

Coccolithophore export in three deep-sea sites of the Aegean and Ionian Seas (Eastern Mediterranean): Biogeographical patterns and biogenic carbonate fluxes

Human follicle-stimulating hormone modulation of adrenal gland activity in the Italian crested newt, Triturus carnifex (Amphibia, Urodela)

Although it has been reported that Notothenia rossii elsewhere hatches in spring, our daily increment back-counting from the capture date in otoliths of fingerlings caught in Potter Cove, South Shetland Islands, in the 2000s, showed two main periods of larval hatching, one in summer (February–March) and another in winter (July). In concordance, the simultaneous presence of two cohorts born the same year was identified in the age/length frequency distribution of fish sampled in spring 2010, which belonged to biological ages 0+ and 1+ and hatched, respectively, in summer and winter–spring. Maximum and minimum ages of pelagic blue-phase and demersal brown-phase fingerlings were, respectively, 227 and 240 days, indicating a demersal settlement after about 8 months from hatching. The estimated growth rate was 0.23–0.33 mm/day, equivalent to that of South Georgia fingerlings and higher than those of other nototheniids of similar size range. Based on early life events associated with the hatching periods, two types of life cycles are hypothesised for South Shetland fingerlings. The pelagic blue-phase fingerlings (6.5–7.6 cm TL, age group 0+) hatched in July (winter cohort), entering in Potter Cove in February–March. The brown-phase fingerlings (6.3–10.6 cm, mostly of age group 0+) hatched in February–March (summer cohort) and were collected in the cove in spring (the smaller specimens) or in summer (the larger ones). Finally, early juveniles (10.7–15.5 cm, age group 1+) hatched in winter, mainly in July (winter cohort), entering in the cove the following year to spend the second winter inshore.

Spatio-temporal variations in organic carbon composition driven by two different major phytoplankton communities in the Ross Sea, Antarctica

Winter months are supposed to be a crucial period for the development of the reproductive system, especially ovaries, in Osmia rufa females. During 7 months of the wintering period (from September till March), the length and width of terminal oocytes and protein concentrations in ovary and fat body tissue extracts of red mason bee females, O. rufa, were studied. Our observations indicate statistically significant differences in the size of terminal oocytes for three different periods of over-wintering: September–October, November–January and February–March. Ovary growth was fast in the September–October period; it slowed down in November–January, and then increased again in February–March. Time-dependent changes were noted also in the number of oocytes and protein concentrations in ovary and fat body tissue during all wintering periods. During all winter months the number of oocytes progressively increased, but a statistically significant increase was only noticed for the periods September–October and February–March. Similarly, during the first two months (September–October) and the last three (February–April) we observed major changes in protein concentration in ovary and fat body tissue. Our results indicate that adult diapause in O. rufa varies to some extent in comparison to the other insects, probably because the the ovary is not fully inhibited during wintering, including the diapause period. These results allow a better understanding of the wintering strategies, including the diapause period, and may be useful for improving rearing methods of this economically important species.

We investigated the possible links between the Barents–Kara sea‐ice area (SIA), Ural blocking, and the North Atlantic Oscillation (NAO) in December–January (DJ) and February–March (FM) using the ERA5 data for the period December 1979–March 2022. The Barents–Kara SIA loss in December is correlated with an increase in geopotential height at 500 hPa (), mean sea‐level pressure (MSLP), and the frequency and intensity of blocking over the Ural in DJ. The Barents–Kara SIA loss in December is also associated with the weakening of the stratospheric polar vortex in FM (particularly in mid‐February) and the negative NAO index. However, our results show that persistent Ural blocking occurs during the transition from a neutral or positive NAO index to its negative phase. Indeed, a significant decrease in NAO index leads to the development of an area of instantaneous blocking (IB) and positive anomalies over the Ural. Persistent Ural blocking contributes significantly to Barents–Kara SIA loss, with a peak decline about seven days after the onset of Ural blocking. The onset of persistent Ural blocking also precedes the weakening of the stratospheric polar vortex by about one month. This implies that the negative correlation between the Barents–Kara SIA loss in December and the NAO index in FM might be caused by the weakening of the stratospheric polar vortex, which itself is induced by persistent Ural blocking. We conclude that the Barents–Kara SIA loss in December can be viewed as a sign rather than the cause of changes in atmospheric circulation over the high‐latitude North Atlantic in succeeding months, because the Barents–Kara SIA also largely responds to Ural blocking and the NAO.

Northeasterly cold surges strongly influence the rainfall patterns over the Malay Peninsula during the northeast monsoon season. This study looks at the changes in the cold surges and Madden–Julian oscillation (MJO) characteristics through the northeast monsoon season and their interaction. Nearly 75% of the cold surge events tend to cross the equator around the Java Sea area (100°–110°E) in February–March with drier conditions prevailing over the Malay Peninsula and increased rainfall over Java. Both the cold surges and the MJO undergo seasonal variations with well-defined regional features. Wavelet analysis shows that MJO amplitude and high-frequency rainfall variations over Southeast Asia peak in November–December. MJO amplitude is suppressed during February and March. This is linked to the high-frequency surges of meridional winds that are prominent during the early part of the season, but February–March is dominated by low-frequency (~20–90 days) cross-equatorial monsoon flow. These prolonged periods of strong meridional flow at the equator interact with the MJO both dynamically and thermodynamically and act as a barrier for convection from propagating from the Indian Ocean to the Maritime Continent (MC). These interactions may have implications for weather and seasonal forecasting over the region. An evaluation of the properties of cold surges and their interaction with the seasonal cycle in the Met Office Unified Model is performed. The atmosphere–ocean coupled model performs better in representing the pattern of influence of the cold surges despite the biases in intensity and spatial distribution of rainfall extremes. These diagnostics are presented with the aim of developing a set of model evaluation metrics for global and regional models.

ABSTRACTVariation in leaf nutrient composition with leaf age and position of leaflets was assessed for ‘Calcuttia’ and ‘Dehradun’ litchi cultivars under loam to sandy loam soils of north India. Leaf samples were collected from first to sixth pair of leaflets starting from the apex of terminal shoots to downward positions during December to May at monthly intervals at two locations for three successive years. The leaves were analyzed for N, P, K, Ca, Mg, Fe, Zn, Cu and Mn concentrations. In both litchi cultivars, leaf N, P, Zn and Cu contents remained more in young leaves; whereas, leaf Ca, Mg, Mn and Fe contents were observed higher in older leaves. Leaf K concentration exhibited inconsistent patterns; however, leaf K concentration in pair of leaflets on the shoot declined basipetal, being maximum in upper pair of leaflets and minimum in lower pair of leaflets. Levels of macro and micronutrients exhibited a degree of stability at second and third pair of leaflets when sampled during February–March. Leaf compositions differed significantly during active vegetative growth, flowering, and fruit development. The results revealed that 4–5 months old leaves from autumn flush at second and third pair of leaflets from the apex of terminal litchi shoots at the advent of panicle initiation (February–March) should be collected to assess the nutritional concentrations of litchi orchards under North India conditions.

In The Birth of the Palestinian Refugee Problem, 1947-1949, (Cambridge and New York: Cambridge University Press. Pp. xx + 380. £30 or $39.50), Benny Morris's overall conclusion that both Arabs and Jews are to blame, at different times and in varying circumstances, for the departure of 'between 600,000 and 760,000' Arabs from Palestine in 1947-1949 cannot be too widely off the mark. Surely, the fair-minded can accept no other conclusion. And this might have been by far the most serious, comprehensive study of a problem whose far-reaching repercussions are all too well known. Yet Morris fails to ahswer the uppermost question in his reader's mind: the Arab flight from Palestine remains buried in mystery, just as it was over forty years ago, when Ben-Gurion noted in his diary after his first visit to Jewish-occupied Jaffa (18 May 1948), 'I couldn't understand: Why did the inhabitants of Jaffa leave?' (p. 101). Morris's answer, which repeatedly ascribes the Arab flight to 'complex' and 'varied' causes, is all too erudite and vague to represent the reality of this momentous event. 'Complex' and 'varied' causes are very useful in dealing with long-term change and development, but they can rarely account for a sudden, major migration. When people flee from their homes, they do so mostly because of a clear cause: fire, flood, earthquake, or their combination. The same can be said of the great migrations of the past: they were created by famine, war and persecution. It is clear that the first 75,000 Arabs who left their homes in Palestine 'by February March' 1948 (p. 30) before the Jewish victories of April deserve centrality and weight in the genesis of Palestinian refugeedom; for they set the flight in train, cast its pattern and initiated what Morris calls Israel's 'ideas about how to consolidate and give permanence to the Palestinian exile' (p. 160). Had these 75,000 not taken to flight, Palestinian and Middle Eastern history would have taken an entirely different course. But if those 75,000 even partly hold the key to this mystery, Morris has disqualified himself from dealing with this chapter, as indeed he has done in every other chapter which makes up the Arab of this tragic story. In his Introduction he laments the 'continued unavailability' of Arab state papers from 1947 to 1949 and the non-existence of Palestinian 'state papers to speak of', recognizing that this lacuna 'leaves the historian burdened by a major problem'. However, it is hard to imagine what good such papers would be to Morris, whose Arabic, at best, is insufficient for the task. This inadequacy not withstanding, he nevertheless promises the reader that he has done his best 'to reduce the area of darkness ... by integrating the Arab side through culling heavily from Jewish and Israeli intelligence reports and from British and American diplomatic dispatches . . . which go a long way towards filling out the picture of what was happening . . . during 1948'. This would still leave Morris with very little to go on regarding policy-making in the Arab capitals; however,

Comparison of β-dimethylsulfoniopropionate (DMSP) levels in two mediterranean ecosystems with different trophic levels