1.1 Overview

The statistical analysis of table XXXX (MRU CWAIS) and table XXXX (CWAIS by countries and sub-countries) indicates largely independent variations of RAIN and BIOMSS, and of TEMP and RADPAR. Altogether, RAIN-BIOMSS account for about 80 percent and TEMP-RADPAR for 20 percent  of climatic variability between January and April 2016. The different patterns also appear when visually comparing figures 1.1 to 1.4. 

The correlation between rainfall and rainfall anomalies is weak (-0.137 for MRUs; -0.060 for countries and countries), indicating independence of anomalies and rainfall amounts, i.e., departures are not specifically associated with high or with low amounts. The same applies to BIOMSS (-0.229 for MRUs and 0.077 for countries), but not to TEMP and to RADPAR; generally correlations between RADPAR and departure from average are positive: larger departures are more associated with high values than with low values (0.577 and 0.678, respectively for n=165).

Figure 1.1. Global map of January – April 2016 rainfall anomaly (asindicated by the RAIN indicator) by MRU, departure from 15YA (percentage)

Figure 1.2. Global map of January– April 2016 biomass accumulation (BIOMSS) by MRU, departure from 5YA,(percentage)

Figure 1.3. Global map of January – April 2016 temperature anomaly (asindicated by the TEMP indicator) by MRU, departure from 15YA (degrees Celsius)

Figure 1.4. Global map of January – April 2016 PAR anomaly (as indicatedby the RADPAR indicator) by MRU, departure from 15YA (percentage)

For TEMP, departures tend to be small (and negative) at high temperatures in the tropics and large (and positive) in temperate regions (-0.616 for 65 MRUs and -0.508 for 165 countries). As was very widely reported in the news,  recent months, and particularly April 2016, broke several temperature records. The fact that low temperatures increase more than high ones (e.g., at high latitudes, or minimum temperature during the day) is consistent with climate warming scenarios.

1.2 Rainfall and BIOMSS anomalies

A. Drought

The recent reporting period witnessed both excess rainfall and drought. As mentioned above, anomaly patterns largely overlap for the RAIN and BIOMSS indicators. Drought, mostly associated with the fading El Niño, affected essentially four areas of agricultural relevance. Additional information is provided for some of them in section 5.XX on disasters. Two large drought affected areas are not receiving any specific attention because they are of very limited agricultural importance (Eastern Siberia, MRU-51, -16 percent rainfall, and Sub-boreal America, C15, -58 percent) and because positive temperature anomalies have somehow offset the effect of low water supply. Problems later in the season, including forest fires cannot be excluded. 

Mediterranean countries

Mediterranean North Africa (MRU-07) recorded on average 74 mm of precipitation over four months, which is very low in absolute terms and 54 percent below average. The amounts of rainfall are insufficient to cover the water requirements of winter crops. In European countries including Turkey (MRU-59), precipitation amounts were larger (225 mm) but nevertheless below average (-15 percent). In the northern Mediterranean, countries also recorded above-average temperature (close to 1°C), which resulted in a biomass production potential drop of 9 percent. In the southern Mediterranean, CropWatch estimates the BIOMSS drop at a significantly higher value of 44 percent.

Punjab and Gujarat to New Zealand

Globally, this is the largest drought affected area, as it extends from southern Asia (Punjab and Gujarat, MRU-48) across India, continental and maritime South-east Asia (MRU-50, MRU-49) and north and east Australia (MRU-53, MRU-54) to New-Zealand (MRU-56). It is also the one where drought was the most severe, even if, due to normally abundant winter and equatorial rains, the agricultural impact in terms of biomass loss is less severe than in some other, drier locations. In continental South-east Asia (MRU-50) RAIN and BIOMSS both drop 44 percent. This is followed, in terms of precipitation deficit, by New Zealand (164 mm, -39 percent) and Southern Asia (MRU-45, 67 mm and -35 percent). The remaining areas recorded precipitation drops close to 20 percent compared with average (Punjab to Gujarat, MRU-48 with 41 mm, -24 percent; Queensland to Victoria, MRU-54, 172 mm or -23 percent; and Northern Australia, MRU-53, 685 mm or -17 percent). In Maritime South-east Asia (MRU-49, 1003 mm and -7 percent) the impact is expected to be minor, not exceeding 10 percent). In Punjab, shared between Pakistan and India, the BIOMSS drop reaches 35 percent. 

East and Southern Africa

Compared with the late months of 2015, a relative weakening of the drought occurred in the East African Highlands and southern Africa. The most severe precipitation deficit was recorded in semi-arid South-west Madagascar (MRU-06, 376 mm and -28 percent) and in the East African Highlands (MRU-02, 181 mm and -20 percent) which includes mainly Ethiopia and the beginning of the Belg rains. The main agricultural areas of Madagascar lost about 13 percent of their average rainfall (MRU-05) but nevertheless recorded close to 900 mm of precipitation, which should be adequate to cover crop water. In the Western Cape province in South Africa (MRU-10), rainfall dropped just 7 percent to 102 mm.

Central and South America

This area—Central and South America—includes MRUs that are not adjacent: one in the south (Western Patagonia, MRU-27) and central and northern South America. Patagonia recorded a noteworthy precipitation drop (-28 percent) in an area and at a time when rainfall is low: just over 100 mm fell from January to April which, associated with a temperature drop (-0.9°C) results is a close to average biomass production potential. In Central and Northern South America (MRU-19), the Caribbean (MRU-20), Central eastern Brazil (MRU-23), and some adjacent areas, the precipitation deficit was close to 10 percent, which is expected to result in a BIOMSS drop between 10 and 15 percent.

B. Precipitation excess

Abundant precipitation in excess of 20 percent above average occurred in several areas (easily identified in figures 1.1 and 1.2.) They occasionally brought local damage to crops and infrastructure through floods, flash floods, and landslides, but altogether their effect was largely beneficial to crops currently in the field as well as those to be planted on soils with ample moisture storage. As with drought, some areas of minor or no agricultural importance are not included in the list below, such as Boreal (MRU-61, +26 percent) and Sub-arctic America (MRU-65, +171 percent), as well as the Australian desert (MRU-63, +52 percent with 148 mm). 

Eastern and Central Asia

This very large area includes much of China as well as some adjacent areas, such as Southern Mongolia (MRU-47, +62 percent precipitation) and Eastern Central Asia (MRU-52, +38 percent). The largest positive anomalies occurred in Inner Mongolia (MRU-35, +163 percent with 111 mm); Southern China (MRU-40, 460 mm, which is about double the average); North-east China (MRU-38, +84 percent); Gansu-Xinjiang (MRU-32, +83 percent); Taiwan, the Loess region, and Hainan (MRUs-42, 36, and 33; +60 to +80 percent); as well as Huanghuaihai, Qinghai-Tibet, South-west China, and the Lower Yangtze (MRUs-34, 39, 41, 37) where the excess varies from 25 to 50 percent. 

North and Central America

Favorable conditions for winter crops or forthcoming summer crops prevailed in the southern United States and North Mexico (Cotton Belt to Mexican Nordeste, MRU-14, 440 mm and +20 percent; South-West United States and Northern Mexican highlands, MRU-18, 107 mm and 41 percent), as well as the Northern Great Plains (MRU-12, 207 mm, +24 percent) and British Columbia to Colorado (MRU-11, 275 mm and +37 percent).

South America

This includes the Semi-arid Southern Cone (MRU-28, 218 mm, +41 percent) as well some of the major soybean and maize producing areas of temperate southern Brazil and Argentina: Central-north Argentina (MRU-25, 583 mm, +25 percent) and the Pampas (MRU-26, 789 mm and +39 percent).

Semi-arid Old World

As mentioned in previous bulletins, the current El Niño conditions seem to be associated with above-average rainfall (about +25 percent) in the west African Sahel (MRU-08) as well as the deserts from the Sahara to Afghanistan (MRU-64). The same area needs mentioning because of minor temperature anomalies of -0.5°C (Sahel) and -0.2 (MRU-64).

Caspian, Black Sea and Eastern Europe

The area includes the adjacent area of the Caucasus (MRU-29, +22 percent) as well as the stretch from Ukraine to the Ural mountains (MRU-58, +45 percent). The area was also characterized by above average temperature, creating altogether favorable conditions for winter crops. 

C. Temperature and RADPAR anomalies

Significantly above normal temperature in excess of 1.5°C occurred mostly over northern North America and east and west of the Ural mountains. Although it recorded a lower temperature anomaly of just 0.8°C, India is mentioned because of its agriculture importance. Below average temperature is mentioned for the Caribbean, southern China, Madagascar, and the Southern Cone from Brazil to Patagonia. A very large area of PAR anomalies affected all of Eurasia, northern Africa and northern North America. The largest negative anomalies include the following: non-Mediterranean Western Europe (MRU-60, -6 percent), the Ural to Altai mountains (MRU-62, -6 percent), and Ukraine to Ural mountains (MRU-58, -11 percent) in the west, up to Taiwan (MRU-42), Southern China (MRU-40), South-west China (MRU-41), and the Lower Yangtze (MRU-37), all at -8 percent, in the east. 

Ural mountains and adjacent areas in mid-latitude Asia

All the areas listed below are characterized by anomalies that reach at least +1.5°C and as much as 2.8°C in MRU-62 (Ural to Altai mountains), 1.9°C in MRU-58 (Ukraine to Ural mountains) and 1.5°C over the area including Western Asia (MRU-31), the Caucasus (MRU-29), and Eastern Central Asia (MRU-52). The area extends east and reaches East Asia (MRU-43; +0.6°C) and Southern Japan and Korea (MRU-46, +0.9°C).

Northern North America

Sub-boreal America (MRU-15, +2.8°C), Boreal America (MRU-61, +5.1°C), and Sub-arctic America (MRU-65, +5.9°C) deserve mentioning because of the extremely large positive anomalies (even if some of them nevertheless record freezing temperature, e.g., Sub-arctic America at -18.2°C). Among areas of agricultural relevance, both British Columbia to Colorado (+2.0°C) and especially the Northern Great Plains (+2.7°C) need listing.

Caribbean, southern China, and Madagascar

Although the listed areas are distant from each other, they are mentioned together because they share some common features, i.e., they are tropical areas and their spatial extension is limited. The Chinese Islands are the locations with the largest negative anomalies recorded for all MRUs (MRU-42, Taiwan, -1.5°C; MRU-40, Hainan -1.4°C), while on the adjacent mainland Southern China (MRU-33) recorded -1.1°C. Two of the areas (MRU-33 and MRU-42) had record negative RADPAR departures of 8 percent. In the Caribbean (MRU-20), the departure was -0.6°C but -1.2°C in South-west Madagascar (MRU-06).

Southern Cone in Latin America

The area covers MRUs 25 through 28: Central-north Argentina (MRU-25, -1.0°C), the Pampas (MRU-26, -0.5°C), Western Patagonia (MRU-27, -0.9°C), as well as the semi-arid southern cone (MRU-28, -1.1°C). Most of them were already mentioned among the areas with excess precipitation. The area also suffered a marked RADPAR deficit reaching -5 percent in the Pampas.